Mass. Gen. L. c. 184, §26 defines "common scheme restrictions" as "restrictions…imposed of record on various parcels in such manner that each owner is entitled to enforce the restrictions against the other parcels, although there may be variations in the restrictions among the various parcels."  This definition essentially codifies the principles previously established by Massachusetts courts, namely that common scheme restrictions may exist notwithstanding slight variations in the restrictions imposed or the failure of a developer to restrict every lot within the affected area.  For cases, see West's Key No. Digests, Covenants, Key No. 77.

The theory of "common scheme restrictions" does not tell you who is burdened by the restrictions - rather, it tells you who is entitled to enforce them.  For a given lot to be burdened by a scheme of restrictions, the restrictions must be contained in the owner's chain of title.  "Common scheme restrictions" provide certain benefited lot owners with the right to enforce the restrictions against affected lots, even though the benefited lot owners were not specifically given the right to enforce such restrictions in their respective chains of title.

Specifically, Mass. Gen. L. c. 184, §26 provides that, unless the instrument imposing the restriction provides otherwise, the following parcels of land will be deemed benefited by the restrictions (i) land bounded by a street by which the subject parcel is bounded, (ii) land lying in a block surrounded by the same streets as the subject parcel, or (iii) land contiguous to such block except for street or ways.