We learned from Cloudflare's https://isbgpsafeyet.com/ that some ASes have deployed RPKI Origin Validation (ROV). However, we downloaded BGP collection data from RouteViews and RipeRis platforms and found that some ROV-ASes can announce some invalid routes. For example, from RIB data at 2022-10-31 00:00:00, 13 out of 17 ASes which declared to deploy ROV announced invalid routes, and we list the number of related prefixes for each AS below.
ASN  	3356	1299	174	2914	6939	3257	6453	3491	9002	5511	7922	13335	16509
pref#	7	23	31	4	361	15	273	16	2	56	17	10	5
As a comparison, we count the invalid routes the non-ROV ASes (also declared in 
https://isbgpsafeyet.com/) announces, as below:
ASN	6762	6461	1273	12956	12389	20485	701	7473	9009
pref#	597	603	587	11	161	162	559	492	380
We can see that ROV ASes announced apparently fewer invalid routes compared to the non-ROV ASes, though they did not filter all the invalids. 
AS6939 announced apparently more invalid routes compared with other ROV-ASes. We learned from the discussions two years ago (https://mailman.nanog.org/pipermail/nanog/2020-June/108309.html) that AS6939 uses reactive ROV. I.e., route collectors identify invalid routes, write them into scripts and send to routers, who then send "withdrawals" of the invalids based on the scripts.
However, for the BGP collection time 2022-10-31 00:00:00, we downloaded the two-hour updates afterwards, and found very few withdrawals from AS6939 about those invalid routes in the first hour. In the second hour, AS6939 withdraws hundreds of invalid prefixes, but most of these withdraws are followed by another invalid announcement with the same prefix and same invalid origin AS.
Can anyone help us to correctly interpret this case? Thank you very much.