During the action at UFC Fight Night 22, WEC matchmaker Sean Shelby tweeted during the prelim fight between Anthony Waldburger and David Mitchell:

Waldburger and Mitchell might set some sort of sub attempt record. What a fight.

Our own Kid Nate added:

Waldburger attempted more subs than I've ever seen tried and failed

So, did they succeed in setting some sort of high mark? From the FightMetric blog:

Congratulations to Anthony "TJ" Waldburger and David Mitchell! Their fight on the undercard of Fight Night 22 set a new UFC record for most combined submission attempts in a single fight (stats available here). Waldburger locked-on seven serious submission attempts and Mitchell locked-on six, for a new record high of 13.

I suppose co-owning the combined sub attempt record is akin to owning a record for most spares in a bowling match, but there you go.

FightMetric's Rami Genauer informed me that Waldburger and Mitchell surpassed the mark set by Cole Miller and Leonard Garcia at UFC Fight Night 11 back in September of 2007. Miller and Garcia "combined" for 10 submission attempts. Rami made sure to note that Miller was credited for all 10 attempts.