Why Cadence buy? The anwser is apparent:
1) In package-level SI and PI analysis, Cadence encouted a powerful competitor, Ansys. Aalso Sigrity are eating Cadence's market share agrresively. To survive, Cadence have to by Sigrity technologies.
2) In board-level SI analysis, now Cadence's SQ is out of gas, so they need new Sigrity technology to compete against Mentor's Hyperlynx suite
Why Sigrity sell?
1) They have much competitors in this niche market. It's very difficult to expand thier market share.
2) Designers prefer the solution to support analysis in design,not do analysis after design. A standalone SI or PI tool is difficult to survie.
How this deal change competition ?
To Ansys, no threat at all, also no threat for Agilent and CST, but for MentorGraphics, this may be a larger threat. I guess next consolidatin may be happaned between Agilent and Mentor Graphics, or CST.