Stripe has significantly lowered its pricing in Europe, and Adyen could be to blame, not just new Europe Union regulations.

Stripe disclosed yesterday that it has cut its interchange fees across 14 nations in Europe by up to 100 basis points, to 1.4% on European cards. Stripe also made other tweaks to its European pricing yesterday. The EU’s caps on interchange went into effect yesterday, too.

Market observers we talked to pointed to another possible cause for Stripe to lower its rates: Adyen, the Dutch payments startup. As one market observer put it, “Adyen must be kicking their ass.”

For the record, Stripe said it was dropping its prices for other reasons:

Stripe is working to grow the size of the internet economy and new regulations from the EU have enabled us to simplify and unify pricing across the European markets we support.

Stripe charges 2.9% in the US.

Adyen reportedly has a larger sales team than Stripe — “this is a huge missing thing with SF-area startups,” one industry consultant said. Adyen is also said to be doing “much” more business than Stripe, “and in some ways is more agile.” Just last month Cathay Pacific Airways selected Adyen for its payments in 45 markets, supporting “250 payments methods around the world.” Adyen reportedly “custom tailors all rates.”

Adyen says it now serves more than 4,500 businesses, including Facebook, Uber, Airbnb, Netflix, Spotify, Dropbox, Evernote, Yelp, Vodafone, and SoundCloud. Last week, Adyen CEO Pieter Van der Does confirmed that Adyen will record “about $45 million” of net income for 2015, and said Adyen expects $90 million to $100 million of net income for 2016.

Stripe, meanwhile, claims to “process billions of dollars a year for thousands of businesses,” including Twitter, Kickstarter, Shopify and Lyft.

UPDATE: A Stripe flak wrote us subsequent to publication of the above blog that “Some of the comments from ‘market observers’ and ‘industry consultants’ are just bizarre and misleading.”