Not filing an opposition brief means the motion is unopposed

Under Title 8 CFR 1003.23(a), if a party does not file a timely opposition, then the motion shall be deemed unopposed.

In Wellington v. INS, No. 95-60795, 108 F.3d 631 (5th Cir. 1997), the Fifth Circuit noted that the immigration judge violated the regulations by not considering a respondent's motion to be unopposed when INS failed to submit a timely opposition brief. However, just because a motion is unopposed probably does not mean that it has to be granted.