Private company

CSR plc

Logo: CSR, Public domain, via Wikimedia Commons4

Former U.K. semiconductor company

CSR plc (formerly Cambridge Silicon Radio) was a multinational fabless semiconductor company headquartered in Cambridge, United Kingdom. Its main products were connectivity, audio, imaging and location chips. CSR was listed on the London Stock Exchange and was a constituent of the FTSE 250 Index until it was acquired by Qualcomm in August 2015.3 It was founded by Phil O'Donovan and James D. Y. Collier.1 Wikipedia text CC BY-SA 4.0

Last updated Oct 21, 2026.

Overview

1998Founded1
  • Industrysemiconductor1
  • HeadquartersCambridge1
  • Websitecsr.com
  • Listed onLondon Stock Exchange1
  • Incorporated inUnited Kingdom5
  • Business addressChurchill House, Cambridge Business Park, Cowley Road, Cambridge, X0 Cb4 0Wz5
Cambridge Business Park CSR
Photo: Cmglee, CC BY-SA 3.0, via Wikimedia Commons7

CSR plc (formerly Cambridge Silicon Radio) was a multinational fabless semiconductor company headquartered in Cambridge, United Kingdom. Its main products were connectivity, audio, imaging and location chips. CSR was listed on the London Stock Exchange and was a constituent of the FTSE 250 Index until it was acquired by Qualcomm in August 2015. The company was since renamed as Qualcomm Technologies International, Ltd.3

The story

Founded by James D. Y. Collier and Phil O'Donovan in 1998.1

The company was founded in 1998 and split away from Cambridge Consultants as Cambridge Silicon Radio or CSR, in 1999. The founding directors, who were all at Cambridge Consultants at the time, were Phil O'Donovan, James Collier and Glenn Collinson. It was first listed on the London Stock Exchange in 2004.

In 2005 the company acquired Clarity Technologies, a leading clear voice capture (CVC) business and UbiNetics, a 3G wireless (WCDMA/UMTS/HSDPA) technology company. In 2007, CSR acquired Nordnav, a Swedish-based GPS software company, and CPS, a Cambridge-based GPS software company producing Enhanced GPS in partnership with Motorola.

In February 2009, CSR announced it was merging with SiRF, the biggest global supplier of GPS chips, in a share deal worth $136 million; in July 2010, CSR announced the acquisition of Belfast-based APT Licensing Ltd. (APT) and its aptX audio technology and in February 2011, CSR announced it was merging with Zoran, a video and imaging technology company.

In May 2012, CSR acquired Direct Digital Feedback Amplifier (DDFA) technology, a proprietary, highly scalable digital Class-D audio amplifier technology; in June 2012, CSR announced that it had acquired the MAPX (formerly MAP-X) audio product line from Trident Microsystems, Inc and in July 2012, Samsung Electronics agreed to acquire CSR's mobile phone connectivity (Bluetooth and Wi-Fi) and location (GPS/GNSS) businesses and associated IP for US$310 million (£198 million). As part of the deal Samsung acquired a stake of 4.9% in CSR.

In June 2014, CSR acquired the people and technology of Reciva, a networked audio streaming platform, for US$5 million and in October 2014, the acquisition of CSR by Qualcomm for $2.5 billion was agreed. The transaction was completed in August 2015.

From Wikipedia’s article on CSR plc, shared under CC BY-SA 4.0.6

Leadership

Who has led CSR plc, and when. Pick a name to see everywhere that person has worked.

Products and brands

  • fabless semiconductor manufacturer

Listed on Wikidata.1

CSR's products included platform solutions for Bluetooth, GPS, FM broadcasting, Wi-Fi, audio, imaging, and ARM processors. After the Zoran merger, CSR also made digital imaging products based on the MIPS architecture.

From Wikipedia’s article on CSR plc, shared under CC BY-SA 4.0.6

Timeline

  1. Aug 2015Dissolved Dissolved1
  2. 1998Founded Founded1

SEC filer profile

How CSR plc is registered with the Securities and Exchange Commission, from its EDGAR record and the cover page of its latest annual report.

  • Name on EDGARCSR PLC2
  • CIK0001368358
  • Employer ID (EIN)98-06166312
  • Incorporated inUnited Kingdom2
  • Fiscal year endsDecember 312
  • Industry code (SIC)3674 Semiconductors & Related Devices2
  • Business addressChurchill House, Cambridge Business Park, Cowley Road, Cambridge, X0 CB4 0WZ2
  • Phone44 (0) 1223 6920002
  • On EDGAR sinceMay 17, 20062
  • Filings705 in all: 6-K (572), 425 (43), SUPPL (10), S-8 (7), S-8 POS (7), UPLOAD (7), 20-F (6), SC 13G/A (6)2
    All 30 form types

    SC TO-C (6), CORRESP (5), ARS (4), 20-F/A (3), EFFECT (3), F-4/A (3), 424B3 (2), 6-K/A (2), F-4 (2), F-6EF (2), SC 13G (2), SC TO-I/A (2), SD (2), 12G3-2B (1), 15-12B (1), 25-NSE (1), 8-A12B (1), 8-A12G (1), CERTNAS (1), CT ORDER (1), F-6 (1), SC TO-I (1)

  • Latest filingsAnnual report (20-F) Mar 20, 2015

Sources

The numbers on this page point here. Each one links to the record it came from.

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