I think one of the reason is LL-IX strips their own ASN (59947) from the path and feed it to the route server. I see it as junk routes, and lots of people forgot(or intentionally not) to add 59947 back.
I scanned all [LLIX members](https://ixp.ll-ix.com/api/v4/member-export/ixf/1.0) this morning([https://i.imgur.com/CsB8I1M.png](https://i.imgur.com/CsB8I1M.png)), only AS140731 is still feeding junk routes generated by LL-IX to the RIS and bgp.tools, I think it's fine to remove AS141011/AS141237/AS147028 from the filter list.
I scanned all LLIX members again, no LLIX members feeds junk routes to RIS now. I think we can remove AS141011/AS140731/AS141237/AS147028 from the filter list now.