Hello
I wonder what companies had in their catalogues / offers the SL lamps. I know that many of these CFLs ih the world were produced by Philips but many companies had it in her offers and there are had different symbols I just know that these CFLs had in catalogues Philips, Osram, Narva, Sylvania, Leuci, Mazda, Tungsram, Hema, GE, Panasonic, Paulmann, Radium, Splendor. But maybe more companies and brands have these CFLs in her offers?

I've got some SL18 labled as Südlicht (German words "süd"=south and "licht"=light) LS18.
The have the same datecodes as Philips ones, I think. (e.g. Datecode M7)

There were also SL lamps re-branded as Sunlux which was the brand of Migros supermarket in Switzerland. Today they don't re-brand any more theirs lamps.