U.S. announced M&A activity in first quarter produced 2,332 deals valued at $192.7 billion, according to data from Thomson Reuters.

This represents a 53% decrease by deal value and a 21.5% slide by the number of deals, Thomson Reuters said.

Private equity backed transactions turned in a shocker. There were a total of 319 transactions valued at $27.7 billion, representing a 6.5% increase by deal value, Thomson Reuters said. However, the number of deals actually declined 5% from 337 announced in first quarter 2011, TR said.

The biggest deal in first quarter was Roche Holding’s bid for Illumina. Thomson Reuters’s is valuing the proposal at around $7.5 billion. [Illumina has since rejected an improved offer from Roche, Reuters is reporting.] While interesting, that’s a strategic deal and this is peHUB.

Here’s a slideshow of the quarter’s top 5 PE-backed deals:

No. 5 Quest Software

The quarter’s fifth largest deal came from Insight Venture Partners. In March, IVP announced it was buying Quest Software in a $2 billion deal. Aliso Viejo, Calif.-based Quest helps companies manage databases and provides other corporate IT services.

Insight focuses on software, internet and data-enabled businesses and can invest from $10 million to $200 million per deal. (The firm is putting $210 million equity into Quest.)

Related posts:

  1. Slideshow: Top 10 PE-backed Deals This Year
  2. Slideshow: Here’s the Top 10 PE-Backed Deals in 2011
  3. M&A Is Heating up; Here Are the Top 10 VC-Backed M&A Deals for Q3 (slideshow)
  4. Slideshow: PE-Backed M&A Jumps in Q3 and Here’s the Top 5 Deals
  5. Value of PE-Backed Tech M&A Jumped 60% in Q2