Yeah, 2500 must the number programmed in. Strange bid/ask action on these as if the programs were trying to make it appear that a rising stock is falling, or vice versa.
Also, sometimes the number of shares also points to some shady trading. Watch for a while. Most folks wouldn't pay $5 to execute a trade for 11 shares of a penny stock. Would you? But there they are with very odd bid/ask action again.