It is a custom implementation of a non-Enterprise Recaptcha, which has V2 and V3 implementations.
Enterprise V3 is identical to non-Enterprise V3
Enterprise V2 combines features of non-Enterprise V2 and V3. Users who solved normal-looking V2 puzzles scored from 0 to 1, the same as V3. A score of 0.1 means the user is "a bot", a score of 0.9 means the user is "a perfect human being". With that in mind, we've added special task queues for Enterprise V2, which consist only of workers with high V3 scores (0.7 and 0.9). Scores like these are pretty hard to achieve even for an average surfer, so you may notice that we have fewer workers at that level, and their work costs more - $5 per 1,000 solutions.
Also, Google seems to provide custom solutions for enterprise customers, tuning their captcha widgets individually for each company. We are aware of such possible "tunings" and offering our customers full support for their emulation. These differences are apparent in what websites use as payload to render Recaptcha widgets.
Non-enterprise widget render call example:
Enteprise widget render call example with custom "s" token:
With our API
you can specify any additional payload data in the enterprisePayload