Curious active filter topology

[ConnorGames]

I was just browsing the web and encountered a strange looking active filter, and have no idea what topology it is or what kind of thought process would be required to create such a filter. Could someone enlighten me about this filter? What topology is it?

I'm just curious and trying to broaden the pool of filter types I have to work from when I'm designing something.

I have attached a quick and ugly ltspice sim. Sorry the components are all bunched up!

[mazurov]

T-network? They need very low frequency for which component values become very large.

[LvW]

I was just browsing the web and encountered a strange looking active filter, and have no idea what topology it is or what kind of thought process would be required to create such a filter. Could someone enlighten me about this filter? What topology is it?

Regarding the topology - it is a special form of a third-order Sallen-Key lowpass with unity dc gain - and rising ac gain.
I didn`t check the gain response  (for the given values) - however, it looks "strange" (if the display is correct).

Remark (edit): You shouldn`t overlook that the part of the original circuit (from D. Johnson) - as sketched by you - is not driven by a low-impedance source (as in your simulation) but by a high-resistive signal source.