Ask HN: Which venture studios have succeeded (and why)?

The venture studio/incubator model (i.e. partners invest time and money to create spin-out NewCos) has been around for ages.

Idealab has been prolific and successful over the past 26 years, but from cursory web searching it seems like there are many other venture studios who are less well known.

Other than Idealab, who is succeeding at spinning out companies that go on to thrive?