The company filed for an IPO with a maximum size of $125 million and contemplates having selling shareholders. Joint book-running managers are Morgan Stanley, Credit Suisse, JP Morgan and BofA Merrill Lynch. [Side note: is it just me or is the whole "joint book-running manager" thing getting out of hand?] Co-managers are UBS, Pacific Crest and Cowen.
Investors in Splunk include August Capital, Sevin Rosen, JK&B Capital and Ignition Partners.
Here's a link to the SEC filing: http://www.sec.gov/Archives/edgar/data/1353283/000104746912000155/a2206835zs-1.htm