Board Thread:Warhammer 40k General Discussion/@comment-5846164-20130912160556/@comment-8881468-20130916225811

in the imperium you have ~ 1000 chapters  standing at 1k a piece

rarest are space wovles because they have no successors (wolf brothers are extinct) although the wolves number more than 1000 marines anyway

the problem was basiccally that when the heresy was finished, the raven guard, salamanders and iron hands were still recovering from the drop site massacre, where they had lost several thousand men each raven guard were few when the 2nd founding came.

now to quote the space marine chapter article

"Each Chapter is created from the gene-seed of an existing donor Chapter. The zygote derived from each type of gene-seed is implanted by the Magi Biologis of the Adeptus Mechanicus in a human test-slave who spends his entire life in a static experimental capsule, immobile and serving as nothing but a medium from which two Progenoid Glands will develop. When the Progenoids are fully developed, they are extracted from the original test-slave and then implanted into another two test-slaves, producing four Progenoids, and so on. It takes 55 standard years of this type of reproduction to create a healthy set of 1,000 new Astartes organs. These must be tested for purity and genetic consistency before they will be sanctioned officially by the Fabricator-General of the Adeptus Mechanicus and then by the High Lords of Terra, speaking for the Emperor of Mankind, who alone can give permission for the creation of a new Chapter."

to quote the space marines articles

"There are approximately 1,000 Space Marine Chapters active in the Imperium of Man at any one time. A list to most of them can be found here. This number has stayed relatively constant since the Second Founding in the 31st Millennium following the Horus Heresy when the First Founding Space Marine Legions were broken up. However, this number remains far from exact and may fluctuate widely depending on the time period and the circumstances confronting the Imperium."

--> aka: legions that made it through the heresy without much loss are overrepresented

gene seed for a new founding can come from different sources, they can combine gene-seed from chapters (as seen in the relictors/fire claws)

there are also sources stating the use of traitor gene-seed (bloodravens,sons of antaeus)

many chapters are also not told their benefactors and not given old wargear..

there are chapters out there that draw gene stock from legions but are not listed as successor chapters, since that needs more connectionthan genes