NYSE: GCTS

Even as more and more applications are deployed on 5G networks, we nonetheless anticipate continued demand for our existing 4G LTE product lineup (4.75G/4.5G/4G, etc.) for the foreseeable future, because 4G products are expected to coexist in the market with 5G products at lower price points for some time in the same way that 3rd generation (“3G”) products coexisted with 4G products when 4G networks were first deployed. We commenced our first production shipments of our 5G products in the fourth quarter of 2025. Also, we expect the average sales prices for our 5G chipset to be approximately four times that of our 4G chipset, resulting in a significant increase in revenue and gross margins. We plan to continuously expand our product lineup to support 5G chipsets for future applications such as vehicle-to-everything standard (e.g., C-V2X), 5G-based satellite communication (e.g., Non-Terrestrial Network), and 5G-based IoT standard (e.g., RedCap). Our current chipset products are used in a wide variety of applications, including fixed wireless subscriber terminals (e.g., CPE), mobile wireless routers (e.g., Mobile Router/MiFi), various communication modules and devices, and industrial products.

Since inception, we have financed our operations primarily through cash receipts from customers, the issuance of convertible promissory notes, borrowings, and the issuance of capital stock.

Evolution of Wireless Technologies

As the demand for mobile communication has evolved from voice-centric to data-centric, technology has continuously evolved. The 1st generation (“1G”) analog cellular system introduced the concept of the cell to facilitate frequency reuse. Due to the limitations of analog technology, the rapidly growing demand for mobile phones led to the transition to 2nd generation (“2G”) digital communication systems. Notable 2G digital mobile phone systems include Global System for Mobile Communication (“GSM”) using Time Division Multiple Access (“TDMA”) and Code Division Multiple Access (“CDMA”). GSM was adopted in Europe, while CDMA was adopted in the United States, Korea, and other regions.

2G had limitations due to the broad mixture of technologies and differences in frequency bands, making international roaming difficult and providing limited multimedia services due to low transmission speeds. The need to unify wireless transmission technologies for international roaming services and more led to the development of 3G mobile communication, such as IMT-2000, W-CDMA, and CDMA2000. 3G not only provided voice and low-speed data like 2G but also supported multimedia services, including video. Up until the adoption of 3G, there was significant demand for circuit-switched services, but as the internet became widespread, the demand for packet services also grew. This led to technological advancements with 3G, resulting in technologies like Evolution-Data Only (“EV-DO”) and High Speed Packet Access (“HSPA”).

Generation

System

Multiple access technology

Peak user data rate

1G

AMPS

FDMA

—

2G

IS-95

CDMA

9600bps

GSM

TDMA

0.104Mbps

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Generation

System

Multiple access technology

Peak user data rate

3G

W-CDMA

W-CDMA

0.384Mbps

CDMA2000

CDMA

0.153Mbps

3.5G

EV-DO

CDMA/TDMA

3.072Mbps

HSPA

W-CDMA

14.4Mbps

4G

LTE

DL: OFDMA UL: SC-FDMA

DL: 100Mbps UL: 50Mbps

WiMAX

OFDMA

DL: 128Mbps UL: 56Mbps

LTE-A

DL: OFDMA UL: SC-FDMA

DL: 1Gbps UL: 500Mbps

5G

NR

OFDMA

Up-to 10Gbps

The increased demand for wireless data services after 3G led to the development of 4G technology, known as LTE. While Worldwide Interoperability for Microwave Access (“WiMAX”) was another 4G technology, the market eventually consolidated around LTE. LTE was defined by the 3rd generation partnership project (“3GPP”), which established the Rel-8/9 standards. LTE later evolved into LTE-Advanced (“LTE-A”) and 3Band LTE-A, including standards like Rel-10 and beyond, which introduced technologies like Carrier Aggregation (“CA”), Coordinated Multi-Point (“CoMP”), relaying, and Multi-Input Multi-Output (“MIMO”).

4G Technology

Features

Carrier

Bandwidth

Downlink peak throughput

LTE

(4G : CAT3)

Technology that is approximately 5 times faster for downloads and about 7 times faster for uploads than traditional WCDMA

10MHz

75Mbps

Wideband LTE

(4G : CAT4)

Mobile communication services that are twice as fast as LTE, utilizing a 20MHz wideband LTE frequency

20MHz

150Mbps

Wideband LTE-A

(4.5G : CAT6)

Mobile communication services that utilize CA (Carrier Aggregation) technology by combining a 20MHz wideband LTE frequency with a 10MHz LTE frequency

30MHz

(20+10MHz)

225Mbps

4x4MIMO LTE-A

(4.5G : CAT5)

Mobile communication services that use 4x4 MIMO (Multiple Input Multiple Output) with 4 antennas to double the speed on a 20MHz wideband LTE frequency

20MHz

300Mbps

3Band LTE-A

(4.75G : CAT12)

Mobile communication services that utilize CA technology to use a 40MHz LTE frequency.

60MHz

(20+20+20MHz)

600Mbps

5G communication evolved from 4G as a communication technology needed for the “Hyper-Connected Revolution” of the Fourth Industrial Revolution, where various industry technologies converge. The Fourth Industrial Revolution represents the convergence of ICT-based technologies and advanced digital technologies, like artificial intelligence, robotics, virtual reality, augmented reality, 3D printing, biotechnology and quantum computing, among others. This technology convergence creates a new era where “people + places + objects + products” are interconnected based on artificial intelligence. 5G is an essential communication technology that enables the Fourth Industrial Revolution and related technology convergence by realizing ultra-fast wireless communication (eMBB: enhanced Mobile Broadband), ultra-low latency reliable communication (URLLC: Ultra Reliable Low Latency Communication), and massive machine-type communication for hyper-connected objects (mMTC: massive machine type communication).

5G Technology

Features

Carrier

Bandwidth

Downlink peak

throughput

Sub-6Ghz (FR1) NR

5G that support frequency bands ranging from 400MHz to 6GHz, offering over 4 times faster response processing than LTE and more than twice the frequency bandwidth

100MHz

2.3Gbps

mmWave(FR2) NR

5G that utilize millimeter-wave frequency bands of 24GHz, 28GHz, and 39GHz, providing over 8 times faster response processing than LTE and supporting over 8 times wider frequency bandwidth

800MHz

(8 x 100MHz)

6.5Gbps

EN-DC (NSA)

5G that transmit data combining both 4G LTE and 5G NR, aggregating them to increase transmission speed and address initial 5G network coverage issues

4G LTE band + 5G FR1 100MHz or

5G FR2 800MHz

3Gbps (FR1)

7Gbps (FR2)

FR1 NR SA

5G standalone mode mobile communication services in the Sub-6GHz frequency band without 4G LTE

200MHz

(100 + 100MHz)

4.6Gbps

FR1+FR2 NR-DC

5G standalone mode dual-connectivity mobile communication services that connect Sub-6GHz frequency band NR and millimeter-wave frequency band NR simultaneously

500MHz

(100 + 400MHz)

6Gbps

5G is now growing in all regions around the world. According to the Ericsson Mobility Report published in November 2025, at the end of 2025, the highest 5G subscription penetration is expected to be in North America with 79 percent, followed by North East Asia at 61

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percent and Western Europe and the Gulf Cooperation Council (GCC) countries, both at 55 percent. During the third quarter of 2025, total 5G subscriptions reached nearly 2.8 billion worldwide, with 162 million added in the third quarter of 2025 alone. Further, it is anticipated that 5G subscriptions will continue to increase, reaching 6.4 billion globally by end of 2031.

Expanding Fixed Wireless Access

Fixed Wireless Access (“FWA”) service provides data and voice (“VoLTE” or “VoNR”) connectivity by connecting data terminals through indoor or outdoor fixed CPE to mobile communication networks, offering services comparable to traditional wired line networks such as xDSL, cable, or fiber optics. The wireless network connection approach is advantageous for quick installation in areas with existing mobile communication infrastructure, especially in regions where installing conventional wired networks is challenging or economically impractical. However, traditional wireless networks face limitations, such as lower speed when multiple devices are connected simultaneously, and the performance of user devices that vary based on the environment or location of such user devices relative to the base station, diminishing their competitiveness compared to wired line networks.

However, recently introduced FWA technologies, including gigabit-speed 4G LTE Advanced or 5G NR (New Radio), offer speeds faster than DSL or cable networks, addressing the shortcomings of traditional wireless connections. Especially in frequency bands above 3 GHz, 5G FWA can deliver service with 100 MHz or more of bandwidth, or in the millimeter-wave spectrum above 20 GHz, 5G FWA can utilize 800 MHz or more of bandwidth, achieving performance comparable to optical fiber communications. This makes FWA an attractive alternative technology that can overcome the significant installation costs associated with fiber optics for new installation areas.

According to the Ericsson Mobility Report (November 2025), by the end of 2025, FWA services based on 4G and 5G will reach 185 million subscriptions. FWA services are projected to grow at an annual rate of ~11.5% (2025-2030 CAGR), reaching over 350 million subscriptions by 2031, which is 1.9 times the number of subscriptions at the end of 2025. 5G-based FWA services are expected to grow even faster with a CAGR of over 31% over the same period. 5G-based FWA subscriptions will be, approximately equal that for 4G by 2027 and will constitute 90% of the total FWA services by 2031. Particularly in the U.S. and India markets is FWA connection growth noteworthy. There is a robust demand for FWA in India with the combined number of connections from Jio and Airtel reaching 12 million as of September 2025. Also in the US, the three largest service providers achieved all-time-high quarterly FWA net adds of

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1.04 million connections in the third quarter of 2025, bringing their combined FWA connections to 14.6 million by the end of the third quarter of 2025.

FWA devices come in two main types: Outdoor CPE (ODU, Outdoor Customer Premises Equipment) which typically includes performance-boosting external antennas for improved wireless signal reception in wider areas, and Indoor CPE (IDU, Indoor Customer Premises Equipment), which can be installed in various indoor locations for user convenience. Outdoor CPE generally offers higher performance; however, it requires external antenna installation and the installation of separate cables to deliver power and data, resulting in higher installation and device costs. By contrast, Indoor CPE, while having the disadvantage of impaired wireless reception due to the scattering and attenuation of external radio signals, offers ease of installation without the need for external antennas or additional cabling work, which results in lower installation and device costs.

Notably, with speeds exceeding 1Gbps and network latency of approximately 1ms or less, 5G communication technology offers faster data throughput and reduced delay compared to wired communication options like DSL or cable. Moreover, the deployment of 5G networks for FWA is facilitated by the presence of existing 5G infrastructure developed by mobile network operators to support mobile broadband services.

This has prompted numerous prominent mobile service providers to view 5G-based FWA as a new growth driver, particularly in light of saturation in the mobile phone market, leading to substantial anticipated subscriber expansion.

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Business Development Overview

The Fourth Industrial Revolution is rapidly unfolding worldwide, driven by the increasing adoption of key enabling communication technologies such as 4.5G, 4.75G, and 5G wireless networks. This growth has led to the emergence of a high-speed wireless internet-based 4.5G/4.75G/5G wireless broadband market and related wireless devices and chipsets. We specialize in providing baseband modems, RF chipsets, and protocol software that enable stable communication on 4.5G/4.75G/5G wireless carrier networks. Wireless modems consist of both hardware components, such as RF transceivers and baseband modems, and software responsible for modem operation, protocol processing and system operation. These elements must work together seamlessly to deliver optimal performance and solutions, making this a critical technology for the Fourth Industrial Revolution. However, there are very few companies globally that can commercialize these technologies, given their high complexity and technological barriers. We have continuously focused on wireless communication product development since our establishment, and believe our core technologies and compatibility testing capabilities acquired during the development and sale of our competitive wireless communication chipsets are unique and not easily duplicated by new entrants in the market. As a result, we believe we have secured a strong competitive position by providing competitive and optimized solutions in the mobile communication market where different generations of technology coexist.

We possess essential core technologies for enhancing the wireless data communication capabilities of competitive 4G/4.5G/4.75G/5G chipsets. We commercialized wireless communication chipset technology using four or eight multiple antennas to achieve outstanding performance improvements in speed, coverage expansion, and interference reduction, earning recognition from top global carriers. We introduced 4x4 MIMO 4.5G chipset technology with four antennas in Japan, followed by commercialization of eight-antenna products in the United States and Europe. RF/modem chipset technology using multiple antennas is particularly vital for FWA services that require stable data communication without interruptions in fixed locations. In countries and regions where it is challenging to install high-speed wired networks, such as optical fiber, due to geographical, technical and economic reasons, wireless broadband FWA using 4G and 5G is an increasingly cost-efficient alternative. This service is rapidly expanding worldwide as a core component of the Fourth Industrial Revolution.

We have commercialized competitive wireless communication chipset products, including 4G/4.5G/4.75G, by actively adapting to the evolution of new wireless standard technologies and developing specialized technologies, such as multi antenna modem chipsets, in close collaboration with major carriers worldwide. In addition, we have taken a proactive role in chipset certification and product validation processes required for stable operation on wireless networks, which allows us to gain further credibility from major carriers.

We have developed and commercialized chipsets for various product categories corresponding to 4G, 4.5G and 4.75G including LTE-based IoT chipsets. In collaboration with a leading worldwide wireless operator (the “Operator”), we are currently developing competitive and innovative 5G chipsets that support 5G sub-6GHz and mmWave spectrums. We have established a close relationship with the Operator for over 13 years. In 2019, we entered into a Joint Development Agreement (“JDA”) with the Operator for the design and development of 5G chipsets for FWA, mobile broadband and modules. Pursuant to the JDA, we agree to perform certain services for and collaborate with such Operator to develop semiconductor chipsets, software and related reference designs, and then supply such items to the Operator and our suppliers. Under the JDA, we are required to perform certain services to achieve specified development milestones, and the Operator is required to pay a one-time payment to us upon achievement of each milestone. The JDA also includes other terms with respect to the supply of chipsets, including most favored status protection for the Operator and our suppliers and certain rebate fees based on worldwide sales of chipsets developed under the JDA. We also agree to grant the Operator various non-exclusive, non-terminable licenses for the use of certain source code and work product developed under the JDA, provided that we retain all worldwide rights, title and interest in and to all intellectual property rights embedded and contained in the chipsets provided to the Operator.

The JDA includes customary representations, warranties and covenants and has an initial term of three (3) years, and thereafter automatically renews for one-year period at each annual anniversary of the effective date of the JDA unless written notice not to renew is provided by the parties 90 days prior to the expiration date. In addition, the Operator may terminate the JDA (i) at any time upon written notice to us; (ii) if our business is materially changed by sale of our business, transfer of control of our outstanding stock, merger or otherwise to a competitor of the Operator; or (iii) immediately upon written notice if there is a material breach of the JDA by us and we fail to cure such breach after 30 days.

As part of this arrangement, we are applying the same multiple antenna reception technology to our 5G chipsets that received recognition from top carriers worldwide for 4G, 4.5G and 4.75G products. We plan to offer three different 5G chipset solutions, taking into account various market demands for performance, functionality, and price ranges, similar to our existing 4G LTE products. We have commenced initial commercial shipments of our 5G chipset products to GCT’s lead customers. Additionally, we differentiate ourselves from the dominant chipset provider in the market by providing customized solutions tailored to the specific needs of wireless carriers.

Our wireless communication chipsets can be used in virtually all wireless broadband data devices driving the Fourth Industrial Revolution, excluding smartphones. Such devices include essential CPE for all wireless broadband FWA services and MiFi that offer

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wireless internet connections sharing via WiFi, even while on the move. Our chipsets can also be adopted into devices such as laptops and tablets, card-type modules that provide communication functionality for IoT and industrial applications, wireless monitoring equipment and wireless smart meters. In addition, we plan to expand our product lineup continuously to support 5G chipsets for future applications such as vehicle-to-everything standard (“C-V2X”), 5G-based satellite communication (Non-Terrestrial Network) and 5G-based IoT standard (RedCap), which can create additional markets with meaningful scale relative to existing broadband markets.

We are among a limited number of companies globally with commercially proven 4G LTE & 5G solutions, leveraging leading-edge multi-antenna modem technology to provide differentiated solutions to wireless operators. High barriers to entry, market pushback against incumbents and political sanctions against certain offshore suppliers have led to few reliable alternatives for 4G/5G modem chipset suppliers. These factors have created a timely opportunity for us to expand rapidly. We plan to maintain collaboration with our existing 4G wireless broadband FWA device manufacturers and partners as they transition to 5G. In the 5G space, we are considered an alternative solution provider with competitive pricing, as other options are limited except for the high-priced products of the top-ranked supplier. In particular, for medium-sized FWA device manufacturers, choosing the leading chipset supplier can create a significant cost burden as it often requires large upfront licensing fees and ongoing royalty payments, after commercialization. Our strategy is to offer the advantage of lower initial licensing costs and no additional licensing fee after commercialization. Moreover, having previously adopted our 4G solution and successfully commercializing it, FWA device manufacturers may find ease and convenience in seamless transition to GCT’s 5G solution. In particular, the strong core technologies offered by us, such as the eight-antenna reception technology for improved efficiency and network coverage expansion, are highly recognized and needed by many wireless carriers and FWA device manufacturers. This can serve as significant motivation for wireless carriers and FWA device manufacturers to adopt our 4G/5G chipsets. In 2024, we made announcements regarding development agreements with FWA device manufacturers that will use our 5G chipsets. These announcements included one regarding an agreement with Kyocera and another regarding an agreement with a “Tier One Telecommunications Supplier.”

Our Competitive Strengths

We believe the following competitive strengths enable us to be a strong 4G and 5G wireless semiconductor provider by effectively addressing the challenges faced by customers:

•
Substantial experience and track record in commercialization of wireless technology: We were one of the first suppliers of 4G LTE chipsets for commercialization in many devices including smartphone, USB dongles, embedded wireless modem and CPE products. Also, we were the first provider of 4.5G 4x4 MIMO LTE chipsets for commercialization in 2015. Our experience and historical track records as a proven supplier provides a strong commercial and technology foundation that will enable us to execute our strategies to become a leading 5G supplier.

•
GCT’s proprietary multi-antenna technology: We were the first eight-antenna LTE solution provider which is uniquely suited to relieve carriers’ looming network overloads arising from rapid FWA adoption. We believe this technology is prized by network operators given that it enables lower infrastructure costs and improved service. We believe we are one of the only suppliers with an eight-antenna solution in entry-level baseband/RF chipsets, positioning us uniquely in the marketplace. Multi-User (“MU”)-MIMO is a network capacity enhanced solution to support multiple UEs (User Equipment such as CPE) with multiple beams from the base station and is usually implemented with Massive-MIMO architecture. MU-MIMO provides the peak throughput for the whole network while Single-User (“SU”)-MIMO provides the peak throughput only for a single user. The best way to implement MU-MIMO is to use Massive-MIMO architecture with multiple antenna array at the base station, which can provide high spectrum efficiency through large multiplexing gain as well as antenna array gain. In MU-MIMO, beam control by the base station is not always perfect. As such, the dedicated beam to a specific UE can cause interference to another adjacent UE nearby. This can result in performance degradation unless there is an appropriate interference cancellation technology on the UE side. Our Multi-Antenna Modem provides superior interference cancellation performance on the UE side, even in the harsh MU-MIMO environment with multiple adjacent EUs, by utilizing eight-antenna reception technology implemented in our cost-effective dedicated hardware modem engine.

•
Longstanding relationships with Tier 1 and Tier 2 network operators worldwide: We enjoy relationships with a global stable of network operators, who in some cases have done business with us for over a decade. These trusted relationships are central to our 5G business plan and our expectations of meaningful deployments in the United States as well as in Europe and Asia. Some of these customers have actively contributed to funding and defining our 5G roadmap in order to obtain strategic access to mission-critical components. In addition to network operators, we have longstanding relationships with ODMs and OEMs who in turn play a critical supply chain function for operators. We believe our proven ability to deliver products to specs and on time positions us favorably as we deploy our 5G portfolio.

•
Highly differentiated & innovative modem architecture: Unlike traditional DSP-based modem solutions, we employ a scalable modular modem design based on optimized data-flow dedicated hardware engines, which provides scalable products with optimized cost structure without the de-featuring approach that other competitors usually take. Adoption of innovative, scalable

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5G modern architecture to expand different product SKUs with minimum design effort and cost allows us to use cheaper wafer process nodes without trading off performance and complexity.

•
Deep knowledge and expertise on wireless system-level architecture and signal processing: Our engineering team has deep and end-to-end knowledge and expertise on wireless system-level architectures and networks in relation to a broad range of wireless technologies including Wi-Fi, 4G/5G LTE and IoT. This enables us to serve as a trusted advisor and partner to wireless carriers, OEMs and infrastructure vendors to optimize the performance of their 4G/5G devices and networks.

•
Fully integrated 4G/5G solutions: We provide the industry with highly integrated 4G/5G system-on-chips, or SoCs, integrating not only the baseband modem and RF but also the application CPU for networking function, which is an essential feature of FWA and can save on total solution cost by eliminating an extra network processor or interface ASIC in the platform.

Products

We have developed and commercialized a portfolio of 4G semiconductor solutions to address a variety of applications and market segments from high performance 4.75G (CAT12) solution to low power, low performance 4G IoT (CAT-M1/NB1). We offer baseband modem solutions to encode and decode data based on 4G protocols that serve as the core wireless processing platform for a 4G device; RF transceivers to transmit and receive wireless transmissions; and highly integrated SoC solutions that combine these and other functions into a single die or package. Our SoC solutions integrate the baseband modem and RF transceiver functions, and in some cases, with an applications processor and memory. This advanced level of integration reduces the size, cost, design complexity, and power consumption of the 4G solution. All of our baseband modem SoC products are provided with comprehensive software, including relevant source code, to enable manufacturers to efficiently integrate our solutions into their devices in a wide variety of environments. In addition, we provide customers with design support. This includes reference designs that specify recommended methods for interconnecting our chips to peripheral devices, such as host processors, memory and RF front-end components. Further, we provide customers with a warranty that our solutions are free from defects in materials and workmanship and will operate in material conformance with the provided specifications, entitling the customer to have the defective product repaired or replaced.

In addition to our various 4G LTE solutions that are currently available to our customers, we have just released a 5G NR chipset and have other 5G NR solutions in development that are expected to become available during 2026. Our products, including the expected availability of those products currently in the design stage of development, are summarized in the table and future roadmap below.

Technology

Product

Type

Function

Expected

Availability

Key Features

4G

GDM7243S

CAT1/4

RF+BB

NOW

Integrated DRAM, multi-band RF

4G

GDM7243ST

CA1/4

RF+BB

NOW

Integrated DRAM, 400MHz~3.8GHz

4G

GDM7243SL

CAT1/4

RF+BB

NOW

Enhancement features, Multi-mode

4G

GDM7243i

CAT-M1/NB1

RF+BB

NOW

eMTC/NB-IoT

4.5G

GDM7243Q

CAT-5/6/7

RF+BB

NOW

2CA, 4x4MIMO, Integrating DRAM

4.5G

GDM7243QT

CAT-5/6/7

RF+BB

NOW

2CA, 4x4MIMO, 600MHz~3.8GHz RF

4.75G

GDM7243A

CAT-12/15

RF+BB

NOW

4CA, 4x4MIMO, 256QAM

4.75G

GDM7243AU

CAT-12/15

RF+BB

NOW

4CA, 4x4MIMO, 256QAM, 600MHz~6GHz

4.75G

GRF7243AU

—

RF

NOW

600MHz~6GHz, 4Rx/2Tx

5G

GDM7259X

FR1, FR2, CAT19

BB

H1 2027

8Rx/4Tx, 8CA, 400MHz FR1, 800MHz FR2

5G

GRF7259NR

—

RF

H1 2027

16Rx/4Tx, 400MHz~7GHz RF

5G

GRF7255IF

—

RF

H1 2026

2Rx/2Tx, 800MHz BW, 7~9GHz IF

5G

GDM7275X

FR1, FR2, CAT15

BB

NOW

8Rx/4Tx, 4CA, 200MHz FR1, 400MHz FR2

5G

GRF7265NR

—

RF

NOW

8Rx/2Tx, 400MHz~7GHz RF

5G

GDM7262X

FR1, FR2, CAT15

BB

NOW

8Rx/2Tx, 2CA, 100MHz FR1, NTN

5G

GDM7235X

Redcap, CAT1

RF+BB

H1 2027

2Rx/2Tx, FR1

Cyclicality and Seasonality

Wireless communication chipsets for FWA devices or industrial IoT modules typically have a relatively long lifespan because they are closely tied to network deployments, which are not easily changed due to significant capital expenditures. However, semiconductor solution sales can be subject to fluctuations over time due to the cyclicality inherent in the semiconductor industry and the supply and demand characteristics specific to this industry. We anticipate that these cyclical conditions will persist. While we have not observed a firmly established pattern of seasonality, business activities in Asia tend to slow down in the first quarter of each year during the Lunar New Year period. This is consistent with potential first quarter softness that other semiconductor suppliers experience in the consumer electronics space as a result of the fourth quarter holiday season (specifically the period from the last week of November to the second week of January). This slowdown could potentially impact our sales and operational results during the first quarter period.

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Regulation

We conduct reviews for all products from the early stages of development to determine whether they qualify as strategic items under the U.S. Department of Commerce’s regulations. We prepare relevant documentation and submit it to the U.S. Department of Commerce for evaluation. The U.S. Department of Commerce reviews the items for Export Administration Regulations (“EAR”) compliance and ultimately assigns an Export Control Classification Number (“ECCN”) for the product, which is required for the export and shipment of products during both the manufacturing process and final product delivery. The assignment and use of the applicable ECCN facilitates lawful export, shipment, and transportation of such products. When an ECCN for a commercial product is classified as a strategic item, it may be subject to stricter export regulations. Therefore, if there is a perceived trend toward easing the classification approval by the U.S. Department of Commerce, we may seek re-evaluation for previously approved products that were classified as strategic items. Where feasible, we aim to have these products reclassified as non-strategic items to minimize regulatory constraints on export activities.

Wireless devices equipped with our modem chipsets must undergo formal certification through official regulatory bodies, as well as specific testing and field verification by network operators before they can be approved for sale by those operators or approved for use on the operators network. Beyond the standard reliability testing for products, many critical aspects related to the performance and functionality of wireless devices are managed and executed by our modem chipsets and software. Therefore, the completeness of the solution provided by us is considered the most essential factor in the commercialization process. We offer chipset solutions that comply with radio certification regulations in different countries. Furthermore, leading mobile operators often implement their own product certification processes to ensure network security, performance optimization, and efficiency. In some cases, particularly with major operators, they may enforce the use of certified chipsets only in their products, even before product certification. We have collaboratively engaged with major operators in North America and Asia on multiple occasions to facilitate chipset certification. This cooperation has resulted in successful chipset certifications with various operators, including Verizon, AT&T, T-Mobile, US Cellular, KDDI, SoftBank in Japan, and the three major telecom operators in South Korea. We continue to pursue ongoing certification for our evolving chipsets to ensure compliance with regulatory and operator requirements, and to make adoption by ODM and OEMs as carefree as possible.

Competition

We believe that our competitive strengths will enable us to compete favorably, particularly in the 5G markets. Companies in this industry primarily compete on the following elements: functionality, form factor and cost; product performance, as measured by network throughput, signal reach, latency and power consumption; track record of providing high-volume deployments in the industry; and systems knowledge.

Companies offering wireless modem chipsets can be categorized into those primarily focused on wireless modem chipsets for smartphones and those, like us, dedicated to wireless modem chipsets for wireless broadband applications including FWA CPE, mobile routers and modules. Qualcomm and HiSilicon, for example, offer wireless modem chipsets for both smartphones and wireless broadband applications. In the mid and low-end 4G wireless broadband market, there are Qualcomm, the Company, MediaTek, HiSilicon and Sequans among others. However, in the high-speed 4G LTE space, such as 4.75G and 5G wireless broadband market, chipsets are primarily offered by Qualcomm, us and MediaTek, while Samsung LSI concentrates mainly on modem chipsets for smartphones (most notably the Samsung Galaxy line). HiSilicon has encountered difficulties in its modem business due to political sanctions, and companies like Sequans are limited to lower end IoT chipset developments and more recently pursued a “micro strategy” based on bitcoin.

We establish high technology barriers by offering highly integrated solutions incorporating RF transceivers, baseband modems, and protocol software. In this field, any issues in either the hardware or software components can impede the progress towards actual commercialization. While some specific components can be sourced through external intellectual property (“IP”) providers, there are no IP companies that can provide turn-key integrated solutions. Consequently, we believe it is highly unlikely for others to replicate all of these hardware and software components, insulating us from competition by newcomers, startups, and other risk factors. A recent example of the challenges in wireless communication chipset development, including baseband modem development, can be seen in Apple’s experience in this space. In their pursuit of 5G modem development, Apple has acquired the entire modem development division of Intel in 2019 (which Intel had created through acquisition of multiple modem companies/divisions), emphasizing that independent development alone is not feasible. Even after acquiring Intel’s modem development division, Apple still ostensibly faces obstacles in development and still primarily relies on Qualcomm’s modem products. Apple released its first attempt at a production modem in the iPhone 16e in 2025 (6 years after acquiring the ongoing Intel development effort). It is benchmarked by third parties as slower in download speeds and it cannot access the FR2 (mmWave) bands.

Accordingly, due to the combined impact of high barriers to entry, market pushback against large incumbents with excessive market power or political sanctions against certain offshore suppliers, there are few reliable alternatives for 4G/5G modem chipset suppliers and this has created a timely opportunity for us to expand rapidly. This has also provided us with high scarcity value as one of only a handful of remaining companies worldwide with commercially-proven 4G LTE and soon 5G solutions.

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Customers

We maintain close relationships with wireless carriers and with OEMs and ODMs who supply devices to those carriers and their end users. We do not typically sell chipsets directly to wireless carriers. Our sales are conducted on a purchase order basis with OEMs, ODMs, contract manufacturers or system integrators, and distributors who provide certain customer communications, logistics and customer support functions.

Sales and Marketing

Our sales efforts are focused on securing design wins at leading OEMs and ODMs for wireless broadband devices. We work closely with key players across the 4G/5G wireless broadband industry to understand their requirements and enable them to certify and deploy 4G/5G solutions in high volume. Our sales force is organized regionally to provide account management and customer support functions as close to customer physical locations as practical. We have a direct sales force consisting of five individuals serving GCT OEM and ODM customers in the Asia-Pacific region, including Taiwan, China, Korea and Japan, Europe, North America and South America. In China, Taiwan, Japan and Korea, we supplement our direct sales team with local distributors and sales representatives who handle certain customer communications, logistics and customer support functions. The headquarters and regional sales teams maintain close relationships with customers, identify distributors, and are responsible for the distribution of our products. They also provide education and support for products, including maintenance. These teams handle customer orders, issue quotations, and negotiate prices.

When customers intend to use our chips for product development, we ensure that technical support from our in-house experts is readily available to them. To address potential concerns or challenges in the production and sales processes, we connect customers with our internal technical teams to resolve any issues promptly, ensuring that they do not hinder the timely realization of revenue. Additionally, we collect real-time information from customers to facilitate monthly demand forecasts and maximize quarterly sales performance.

Our sales force is complemented by a team of field applications engineers (“FAEs”) that assists customers in solving technical challenges during the design, manufacturing implementation and certification phases of a customer’s product life cycle. This high-touch approach allows us to facilitate the successful certification and acceptance by the wireless carriers of our customers’ products, which speeds time-to-market for our customers and reinforces our role as a trusted advisor to our customers.

Our sales cycles typically take 12 months or more to complete and our solutions are generally incorporated into our customers’ products at the design stage. Prior to an end customer’s selection and purchase of our solutions, our sales force and FAEs provide our end customers with technical assistance in the use of our solutions in their products. Once our solution is designed into a customer’s product offering, it becomes more difficult for a competitor to sell their semiconductor solutions to that end customer for that particular product offering given the significant cost, time, effort and risk involved in changing suppliers. In addition, we believe that upon achieving a particular design win with a customer, our ability to achieve other design wins with that same customer increases significantly.

Our marketing strategy is focused on enabling broad adoption of 4G/5G solutions and communicating our technological advantages to the marketplace with a focus on wireless carriers. This includes building awareness of and preference for our technology at wireless carriers who generate demand for 4G/5G-enabled devices. By working to understand carrier services strategies, device roadmaps and technical requirements, we believe we are better positioned to drive our roadmap to meet these needs, to influence carriers’ choice of technology suppliers, and to identify manufacturers in the wireless industry who are best prepared to serve the needs of the wireless carrier.

Our marketing team is also responsible for product management, strategic planning, product roadmap creation, OEM, ODM and wireless carrier business development and corporate communications. All of these functions are aimed at strengthening the competitiveness of our solutions in response to evolving industry needs and competitive activities, and at articulating the value proposition of our technology throughout the 4G/5G broadband wireless industry. Our sales and marketing organizations work closely together to ensure that evolving industry requirements are reflected in our product plans, and that customers have early access to our roadmaps and can communicate the value of our technology to the wireless carriers. This end-to-end value chain management approach is designed to preserve and grow our market share in the segments we serve. Based on the execution of our sales and marketing strategy, we have achieved a history of commercialization success, as described below.

Intellectual Property

We rely on a combination of intellectual property rights, including patents, trade secrets, copyrights and trademarks, and contractual protections, to protect our core technology and intellectual property. As of December 31, 2025, we hold approximately 86 patent rights in relation to 5G/4G and next-generation wireless communication semiconductor technology. Our patent portfolio consists of modem design-related technologies (58 items, 68%), which includes multi-antenna solution for modular modem design and interference cancellation technology, system impairment (such as IQ mismatch) calibration technology, communication system technology and signal processing modem technology, RF transceiver technologies (20 cases, 23%), frequency synthesis technologies (8 cases, 9%).

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Most of the issued patents have been already applied to our commercial products. Among those patents, there are three key aspects: multi-antenna modem solution which provides scalable, module modem core design technology and base line architecture of our 4G and 5G modem; impairment calibration technology to compensate system impairment from direct-conversion RF and analogy parts, such as I/Q imbalance and carrier leakage, calibration technology; and RF transceiver architecture and related circuit technology for CMOS direct-conversion RF technology. In addition to our U.S. patents, patents have been issued in multiple countries where production facilities, product markets, and competitors are located. As of December 31, 2025, we hold 34 US patents, 34 Korean patents, 7 Taiwanese patents, 5 Japanese patents, 4 Chinese patents, and 2 patents issued in other countries.

In February 2024, we entered into a Foundry Product Development Agreement and related agreement (the “Alpha Agreements”) with Alpha Holdings Co., Ltd. (“Alpha”), pursuant to which Alpha agreed to develop and deliver to us various semiconductor products (produced in the Samsung foundry), including performing certain development activities based on our design data and delivering prototypes in the quantity specified by the applicable statement of work. The term of the Alpha Foundry Product Development Agreement is three years from the date of execution and the total development costs that we will pay to Alpha under this Agreement are approximately $7.6 million. Under the Alpha Agreements, Alpha also granted us a license to use certain third-party intellectual property that will enable us to develop and deliver 5G products set forth in such agreements. Furthermore, also in February 2024, we entered into several license and development agreements with third-party vendors (the “Vendor Agreements”), pursuant to which these vendors agreed to supply us a license to use certain intellectual property that will enable us to develop and deliver 5G products under the Alpha Agreements. As disclosed previously, we entered into a research and development agreement (the “Samsung Agreement”) with Samsung Electronics Co., Ltd (“Samsung”) in July 2020, pursuant to which Samsung agreed to provide us with certain development support, an intellectual property license, and mass production set up support to enable us to develop and produce 5G chipsets for our customers. The development support, technology licensing, and other services provided to us under the Alpha Agreements and Vendor Agreements are intended to support our continued development and production of 5G chipsets utilizing Samsung foundry processes. In connection with entering into the Alpha Agreements, the Samsung Agreement was terminated.

Manufacturing

We employ a fabless semiconductor business model and use third-party foundries and assembly and test vendors to manufacture, assemble and test our semiconductor solutions. Our main foundry vendors are Samsung Foundry, and United Microelectronics Corporation (“UMC”). From Samsung Foundry, we currently use 28nm mixed-signal and digital Complementary Metal-Oxide-Semiconductor (“CMOS”) production processes for 4G baseband modem, and 8nm technology for 5G baseband modem products. The use of these commercially available standard processes enables us to produce our products more cost-effectively and, by migrating to lower process geometries, we expect to achieve advantages in cost, size and power consumption. Particularly, given the fact that foundry companies, which can provide the leading-edge foundry technology for fabless semiconductor companies to access, are very few and practically limited to TSMC and Samsung Foundry in this market, it is very important for us to establish close relationships with such foundry companies. Currently, the Company and Samsung Foundry enjoy a mutually beneficial foundry relationship providing secure access to leading-edge technology and manufacturing capacity as our 5G business ramps.

From UMC, we currently use 110 RF production process for 4G RF only, and 40nm RF, mixed-signal and digital CMOS production processes for 4G baseband, 4G RF and 5G RF. From TSMC, we currently use 40nm RF, mixed-signal and digital CMOS production processes for 4G RF only.

We use Hana Micron, Stats ChipPAC, and Advanced Semiconductor Engineering, Inc., (“ASE”) for most of our assembly and testing requirements on a purchase order basis. We conduct extensive simulation, practical application and standardized test bed studies to validate and verify our products.

We closely monitor the production cycle from wafer to finished goods by reviewing electrical parameters, manufacturing processes and test yield data. We also run routine reliability monitoring programs to ensure long term product reliability. This enables us to operate certain test processes on demand to reduce the time-to-market for our products and to help ensure their quality and reliability. The Company and all of our outsourcing partners have implemented and adhered to the quality management system and environmental management system as required by ISO 9001:2015 across the organization. This has enabled the establishment of a robust quality assurance system for production and products, securing trust from our customers. We are also proactively responding to the strengthening of international environmental regulations and meeting market demands.

Human Resources

As of December 31, 2025, we had 126 full-time employees, of whom 101 were located in Korea, 18 were in the United States, three were in Taiwan, two were in China and one was in each of Hong Kong and Japan. These employees include 80 in research and development, 18 in sales and marketing, 22 in general and administration and 6 in operations. Management considers labor relations to be positive. We also contract with independent contractors and consultants.

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Facilities

Our principal executive offices are located in San Jose, California, and consist of approximately 5,900 square feet under a lease that expires in October 2026. This facility accommodates our product marketing and finance and administrative activities as well as a small research and development team. We have an approximately 56,500 square-foot facility in Seoul, Korea, which accommodates a research and development center under a lease expiring in December 2026. We have an approximately 100 square-foot facility in Taipei, Taiwan, which houses sales and technical support personnel, under a lease that expires in July 2026. We also have an approximately 850 square-foot facility in Shanghai, China for sales and technical support personnel under a lease that expires in July 2026 and an approximately 720 square-foot facility in Shenzhen, China, which accommodates sales and technical support personnel, under a lease that expires in June 2028.

We do not own any real property. We believe that our leased facilities are adequate to meet our current needs and that additional facilities will be available on suitable, commercially reasonable terms to accommodate any future needs.

Legal Proceedings

We are not currently a party to any material legal proceedings. From time to time, we may, however, in the ordinary course of business become involved in legal proceedings. Regardless of outcome, litigation could have a material adverse effect on us due to defense and settlement costs, diversion of management resources, negative publicity, reputational harm and other factors, and there can be no assurances that favorable outcomes will be obtained.

Available Information

We file Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, proxy statements, and related amendments, exhibits and other information with the Securities and Exchange Commission, or the SEC. You may access and read our filings without charge through the SEC’s website at www.sec.gov or through our website at https://investors.gctsemi.com/sec-filings, as soon as reasonably practicable after such materials are electronically filed with or furnished to the SEC pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended, or the Exchange Act. Information contained on, or accessible through, our website shall not be deemed incorporated into and is not a part of this Annual Report.

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