Yes Motorola originated this part and a whole laundry list of zener based references, some of which live on in various newer reincarnations such as the LTFLU (you might call it the grandchild). There were several pages of data sheets on various reference zeners and reference amplifiers (aka the SZA263 that eventually morphed into the LTFLU).
Besides the many zener references such as the 1N82xA series, 1N4565-1N4580, 1N3154/A, 1N4775/A, 1N4780/A, series1N935A/B/C, 1N216xA series and 1N941/A-1N945/A series
The precision ref zener series MZ605, MZ610, MZ620 and MZ640
Amplifying regulator diodes, MCA1911 - MCA2234
Low voltage zeners, MZ2360/61
Plus a host of house numbered variations like the SZA263.
Today, the LTFLU is only sourced by Linear Tech and sold only to Fluke, any of these that show up on the flea bays are either from recycled/resold equipment or fakes. How the LTFLU 'legally' found its way inside a TEK piece of gear is up for speculation, perhaps a quiet agreement between TEK/Fluke/LT but Fluke was the only buyer of these that I had heard of.
Yes I'm aware that ADI took over LT but it is still LT making these parts, ADI doesn't make them. No I didn't like the take over, I think ADI is messing LT up.