Dive Brief:

• Between June 2013 and July 2014, ad tech companies made up 6% of global tech IPOs—and there has not been a single one since, and only one other filing has gone public since then.
• The drop-off is attributed to ad tech companies not faring well on Wall Street. Tremor Video, which opened at $10 per share, is going for around $2 per share nowadays. Four out of seven companies that went public during the heyday last year are also trading well under opening prices.
• MaxPoint Interactive, a marketing automation firm, filed for an IPO on Tuesday, making it the first ad tech firm to file in almost a year.

Dive Insight:

Ad tech is clearly not going away, so the drop off on Wall Street is likely a sign of hesitation as the market finds its footing. The pool of ad tech companies keeps getting bigger and broader, so investors are waiting as the cream rises to the top.

"Investors are having a tough time understanding what an ad-technology company is," Tim Vanderhook, CEO of ad-tech company Viant, told AdAge. "Until they figure out what that is and the valuations settle down, then I think everyone is pausing on where they're going."