Software developers who do not hold user funds will no longer be treated as brokers when connecting users to regulated markets.
Consumers will still pay nothing, but larger merchants will face a 0.4% charge on high-value transactions from October.
Large late-stage investments drove an 11% week-on-week increase, with satellite and wellness firms leading the charge.
The company plans to expand its mobile authorisation network to every US region within 18 months.
