From Minecraft Wiki
 Staking a claim: ideas for discouraging griefing in Survival Multiplayer
Suspecting something like this is already in server mods (not counting role-playing). The Lands Claim Office.
 Claiming land ownership
- The SMP server is divided into single-player areas, essentially, grid squares 64 or 128 on a side, height & depth unlimited.
- Each player is entitled to 1 "claim stake" which can be placed on any unclaimed square, and which thus becomes their spawn point and home base. (Similar to concept behind US Mining Act.)
- On unclaimed "wilderness" areas, anything goes; mining, PvP etc. On your claim, only you (and co-owners) build and mine.
- Your claim stake can be moved (old spawn point will be used until new one placed).
- The only way to get more than 1 area is to go into partnership; each new shared claim recognized by the server gets one claim stake. (But who gets it? Trust issue. Partnership offers. Shell accounts limited by need to have a paid Minecraft account.) This drives co-op gameplay (which most group servers have in spades already) and makes it harder to directly give a monetary value to a claim stake.
- 3-way, 4-way shared claims?
- N8 allowed for claim-jumping, namely busting up shrines if you can get to them. I'd advise against the feature.
 Actions on another's claim
- On claimed areas, if you are NOT the owner, you get no building/breaking/mining rights.
- Pickups OK if someone drops them for you.
- Griefing possibilites to be tiger-teamed.
- Using chests and crafting? Probably not. True public chests should be placed in wild areas. More thought required.
- Using doors?
- Dropping items (temporarily) on pressure plates etc?
- Flint & steel & fire = grief. No.
- Killing animals or mobs eg in self-defence? OK maybe. You did fall into that zombie pit.
- Aggro'ing mobs and lead them into someone's house...
- Placing or riding minecarts? Too many minecarts...
- Looking around galleries and other spaces deliberately left public is the main intent of allowing others in at all.
 Common Areas
- These are areas belonging to the admin, unlike unclaimed "wilderness". Could also be an in-game menu.
- Trading Post. Important idea (similar in WoW) where you can take advantage of your hard work or plentiful material to trade for things less rare. EG trade with farmers for bread if you have lots of coal. Requires balancing. Note free market forces will drive exchange rate, but are themselves driven by the game's RNG/drop frequency.
- Auctions might be another means for the above but time-consuming, better for rare items like diamond armor.
- Bank Vaults might store material used for payment in auctions.
- Raises idea of in-game currency and even exchange rate with real-world currency like 2nd Life; I'd advise against feature.
- Protected Thoroughfares? Will this arise naturally in community (every participant sets aside 3 tile wide road area) or should it be squeezed between claimable boundaries? eg by Admin? PvP and building/breaking not wanted here. eg newb spawn point.