Prior to the JOBS Act, sell-side analysts were prohibited from publishing research before the IPO, for 40 days after the IPO, and in the 15 days before and after lock-up agreements with pre-IPO stockholders and the company expire.

FORBES: On Its One-Year Anniversary, Two Cheers For The JOBS Act

Pre-IPO investors who came in at high valuations want the company to list at even higher ones.

CNN: Playing the IPO Game