It was back in September 2003 when Cadence exited the ESL space. At that time Penny Herscher, then executive vice president and general manager at Cadence, said "From now on, if a Cadence customer asks for ESL tools, we will refer them to CoWare,"

With that deal Cadence granted CoWare an exclusive license to sell and develop Cadence's Signal Processing Workstation (SPW) tool although Cadence retained their intellectual-property rights to this. In addition Co-Ware took over Cadence's ESL group. CoWare was to pay Cadence a royalty for SPW tool sales, which I imagine is in doubt now, but not clear if Cadence will not regain ownership of that.

Cadence did have an equity stake in CoWare, but it is not clear who percentage that was, or if they still hold that stake. If they did, then it would presumably mean that Cadence was aware of this acquisition by Synopsys and chose to do nothing about it.

The company's investors included the Belgium-based Interuniversity Microelectronics Center (IMEC) -- from which CoWare spun off in 1996 – and they received almost $14 million in venture capital funding in two rounds of funding from Greylock, Needham & Company($11.5M), GIMV and IT Partners. Then ARM, ST Microelectronics and Sony provided another $14M. Another known investors was Excelsior Equity Partners.

Back in 2005, CoWare was attempting to go public and expected to raise between $20M and $100M. This never happened and there have long been grumblings about how much longer they could last without a significant injection of capital.

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Brian Bailey - keeping you covered