The OEIS is looking to hire part-time people to help edit core sequences, upload scanned documents, process citations, fix broken links, etc. - Neil Sloane, njasloane@gmail.com
12 is in the sequence because the product of the run lengths in the binary representation of 12 is 4, and no number less than 12 has a binary run length product of 4.
CROSSREFS
Cf. A167489 - Product of run lengths in the binary representation of n
Cf. A167490 - Smallest number with binary run length product = n