Not sure. Could be numerous things if they're showing a 5K ask, but actually selling 10X, 20X, 50X, 100X, etc... the 5K.
1. AON order & not showing full ask
2. Firm just not showing full ask/Games
3. Firm shorting/naked shorting/Games to hold
4. Firm selling to themselves for a multitude of reasons
5. Etc...
Can't really tell from just L2, but I think that a very large AON order would be the only legit reason.
$ENZC