With Wall Street largely closed to new companies since early last year, there's been wide expectation there would be an especially active merger-and-acquisition market involving late-stage startups as venture investors sought some way of realizing their investments.
That hasn't happened.
In fact, in the first quarter, the combined value of all the mergers and acquisitions involving venture backed companies was just $3.7 billion, according to data from PitchBook. That was the lowest quarterly total…