The companies with in-house R&D in Sunnyvale are primarily mid-sized to large firms specializing in software development, cybersecurity, and semiconductor manufacturing. Key players include Synopsys Inc, which provides silicon and systems design solutions, LinkedIn, connecting professionals globally, Fortinet, a computer and network security firm, and Juniper Networks, developing intelligent networking products. These companies reflect a concentration in high-tech sectors, particularly those focused on digital infrastructure and security.
A notable pattern among these companies is their strong presence in foundational digital technologies. Many, like JFrog, which offers a software supply chain platform, and Applied Intuition, a vehicle software supplier, focus on enabling other industries through specialized software and hardware. The majority of these firms were founded between the late 1990s and mid-2000s, indicating a mature yet continuously evolving technology hub.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
Synopsys Incsynopsys.com
It provides comprehensive silicon and systems design solutions, partnering with customers to enhance R&D capabilities and drive innovation across industries. |
27,809 | |||
| 2 |
LinkedIncareers.linkedin.com
It connects professionals globally, offering services like Talent Solutions, Marketing Solutions, Sales Solutions, and Premium Subscriptions for productivity and success. |
23,635 | |||
| 3 |
Fortinetfortinet.com
Fortinet enables trust in the digital world by protecting people, devices, and data for enterprises, service providers, and government organizations |
16,304 | |||
| 4 |
Juniper Networksjuniper.net
Develops intelligent, agile, and secure networking products and solutions serving global service providers, enterprises, and government organizations worldwide. |
9,059 | |||
| 5 |
Proofpointproofpoint.com
A company specializing in cybersecurity and compliance solutions, protecting people across email, web, cloud, and social media channels effectively |
5,200 | |||
| 6 |
Cepheidcepheid.com
Healthcare company pioneering molecular diagnostics with automated systems and tests for a wide range of infections, diseases, and oncology, delivering actionable results Partnered with industry leader for expertise and solutions |
4,675 | |||
| 7 |
Amazon Lab126amazon.jobs
A San Francisco Bay Area team that designs and engineers consumer electronic devices such as Fire tablets, Kindle e-readers, and Amazon Echo |
4,136 | |||
| 8 | 2,417 | ||||
| 9 |
Finisar Corporationcoherent.com
Follow us at the provided link for updates and information about our rebranding as Coherent Corp Exciting changes ahead! |
1,709 | |||
| 10 |
Applied Intuitionappliedintuition.com
Vehicle software supplier accelerating safe and intelligent machines globally through simulation and validation platforms for automotive, trucking, and construction industries Headquarters in CA |
1,593 | |||
| 11 |
RUCKUS Networksruckusnetworks.com
The company builds purpose-driven networks for industries with high-performance wireless and wired solutions, IoT, assurance, security, and AI-driven software for exceptional connection experiences |
1,388 | |||
| 12 |
Fujitsu Americasfujitsu.com
Leading provider of IT services and solutions globally, specializing in consulting, systems integration, managed services, cloud services, and server technologies, with a focus on sustainability and innovation |
1,173 | |||
| 13 |
Spansion is Cypress Semiconductorinfineon.com
A leading semiconductor company offering high-performance solutions for embedded systems in automotive, industrial, networking, consumer, and mobile devices worldwide |
1,097 | |||
| 14 |
Cerebrascerebras.ai
Accelerating deep learning through cutting-edge technology, including the fastest AI computer with a revolutionary chip for faster neural network training Join our team! |
930 | |||
| 15 |
Mellanox Technologies
A leading supplier of high-performance InfiniBand and Ethernet interconnect solutions for servers and storage, accelerating application run time and maximizing business results |
840 | |||
Want more companies than this list?This page shows the largest ones only. Connect to Tamtam to see every company that matches, filter by size, industry or growth, and reach their decision-makers. | |||||
| 16 |
Crestacresta.com
It enhances contact center performance using generative AI for real-time insights, coaching, and tracking agent interactions to improve efficiency. |
727 | |||
| 17 |
Jumio Corporationjumio.com
Provides AI-powered identity intelligence, anchored in biometric authentication and automation, to establish and maintain trust for organizations and fight fraud. |
613 | |||
| 18 |
Pharmacyclics, an AbbVie Companypharmacyclics.com
A biopharmaceutical company focused on developing novel cancer therapies to improve patient outcomes and address unmet medical needs |
590 | |||
| 19 | 555 | ||||
| 20 |
TiDB, powered by PingCAPpingcap.com
Leading open-source distributed SQL database, powers modern applications with elasticity, versatility, reliability for world-renowned organizations. |
508 | |||
| 21 |
Real-Time Innovations (RTI)rti.com
RTI provides infrastructure software for intelligent distributed systems, supporting various industries including automotive, defense, energy, and healthcare with advanced technologies. |
507 | |||
| 22 |
Alpha & Omega Semiconductoraosmd.com
A global supplier of power semiconductors specializing in Power MOSFET, IGBT, IPM, and Power IC products for various advanced electronic applications |
467 | |||
| 23 |
Ceribell │ AI-Powered Point-of-Care EEGceribell.com
A revolutionary AI-powered EEG system improving seizure management in acute care by providing rapid, accurate diagnostic information and continuous monitoring |
408 | |||
| 24 | 280 | ||||
| 25 |
JSR Micro, Inc.jsrmicro.com
A global provider of innovative semiconductor, life sciences, and energy materials, leveraging polymer expertise to address unique challenges across industries |
266 | |||
| 26 |
Lens Technology Inc.hnlens.com
High-tech manufacturing enterprise specializing in smart device components using various materials for appearance and functionality, serving global consumer electronics and automobile industries |
75 | |||
| 27 | 46 | ||||
| 28 |
DynoSense Corpdynosense.com
A medical technology company focused on creating innovative products and services for a better, longer, and healthier life |
11 | |||
| 29 |
Modified Polymer Components, Inc.modifiedpolymer.com
Specializing in design, rapid prototyping, and manufacturing of precise components for Medical Device OEMs and various other industries since 1989 |
9 | |||
| 30 |
PYROMERAL Technology Incpyromeraltechnology.com
The company specializes in high-temperature ceramic composite components, offering practical, cost-effective alternatives with superior mechanical properties for various industries |
4 | |||
Turn this list into pipeline
Tamtam finds the decision-makers at every company on a list like this one, with verified emails, phone numbers and the buying signals that tell you when to reach out.
How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Nov 12, 2026.
More company lists in Sunnyvale
- The largest companies in Sunnyvale 165
- Multinational companies in Sunnyvale 51
- SaaS companies in Sunnyvale 42
- Software Development companies in Sunnyvale 41
- AI companies in Sunnyvale 31
The same list elsewhere in United States
- Companies with in-house R&D in the United States 6,796
- Companies with in-house R&D in California 1,275
- Companies with in-house R&D in Texas 442
- Companies with in-house R&D in New York State 419
- Companies with in-house R&D in Massachusetts 396
- Companies with in-house R&D in Illinois 322
- Companies with in-house R&D in Michigan 287
- Companies with in-house R&D in Ohio 277
- Companies with in-house R&D in Pennsylvania 255
- Companies with in-house R&D in New Jersey 224
- Companies with in-house R&D in Florida 221
- Companies with in-house R&D in Alabama 215
- Companies with in-house R&D in Georgia 173
- Companies with in-house R&D in Virginia 166
- Companies with in-house R&D in North Carolina 158
- Companies with in-house R&D in Wisconsin 154
- Companies with in-house R&D in Minnesota 146
- Companies with in-house R&D in Washington State 140
- Companies with in-house R&D in Colorado 113
- Companies with in-house R&D in Maryland 107
- Companies with in-house R&D in Indiana 104
- Companies with in-house R&D in New York 223
- Companies with in-house R&D in San Francisco 147
- Companies with in-house R&D in Houston 129