Mashery was acquired by Intel [1] in April 2013, Layer7 was acquired by CA Technologies [2] the same month.

[1] https://techcrunch.com/2013/04/17/source-mashery-is-selling-... [2] https://techcrunch.com/2013/04/22/ca-acquires-layer-7-techno...

3Scale was acquired by Redhat (not IBM): https://www.redhat.com/en/about/press-releases/red-hat-acqui...

My day job used 3scale. Actually it won out against apigee, mashery, and a few other big players. My day job liked a few others because they were associated to "big enterprise names" - especially since my day job is a big enterprise. I think 3scale were still kind of pricey, but way cheaper than the other big players...However, I give big kudos for 3scale support, especially during on-ramping.

IBM bought Strongloop last year as an API gateway play.

The major acquisitions in this space already happened...

CA bought layer7. Mulesoft bought programmable web. Intel bought and divested mastery. Microsoft bought Apiphany.

The last one standing is Akana, (formerly SOA Software).

APIgee was always a weird company to go public - I think it makes sense for them to be part of google. More of a feature that belongs in some other cloud management stack.

Layer7 was acquired by CA Tech a few years ago

Fastly is the biggest one left independent I think. They've got some top clients like github.