Hi,
in the opencv_3rdparty repository there are several pretrained face detector models, e.g.: opencv_face_detector_uint8.pb, res10_300x300_ssd_iter_140000_fp16.caffemodel, etc. But there is no license specified for those (or any other I've checked) models, which renders them useless for any commercial use.
So the question is, what is the license?
Related question: https://answers.opencv.org/question/201189/dataset-used-for-training-dnn-face-detector/