From an entitlements perspective all that is needed for activation is eligible land. It does not matter if that land is part of a field, as long as no one else claims on it.
If a single block of land is farmed by three farmers, then it will be provided with a single parcel number. All three applicants should use the same parcel number, but a different suffix.
The RPA recognises part-parcels with temporary, non-physical boundaries splits by assigning a suffix. The sum of the part-parcel areas indicated in C5 on these three SPS applications should not exceed the total field area indicated in C3.
Although the RPA does not stipulate that sketch maps must be submitted for part-parcels, it would be helpful to indicate the location of the part-parcel, with non-physical boundaries clearly mark as “temporary boundary”.
From a cross-compliance perspective, if non-compliance was discovered in one part of the field, it would be recorded against that claimant only.