It is generally understood that monasteries in Thailand are owned by the Sangha as a whole, and administered by the local Sangha, especially the abbot. The Sangha as a whole here is not the ‘Sangha of the Four Quarters’, but the Sangha as legally recognized under the jurisdiction of Thai law, that is, the ‘Thai Sangha’.
In fact the situation is complex. While in Thailand I stayed in formally recognized monasteries, in hermitages in national parks occupied under an agreement with the national Parks authorities, and in little places that were in fact likely to be just squats. In some cases the land is originally made over to the monastery from the ‘commons’ owned by the local villagers; in other cases it is purchased from a single owner. The actual title owner of the land may not be clear in every case.
The Thai Sangha Act is not particularly helpful in this regard, and seems to take the question as a matter of course. Probably it is handled largely through custom and the decisions of the central authorities.
Here are some of the relevant statements from the first and the current Thai Sangha Acts. I include some passages from the outdated Act of 1902 as it clarifies some points omitted in the later versions. In particular, it clarifies that the ownership of a monastery is transferred from the (presumably lay) donor to the Sangha. And in the critical question of the election of the abbot, it stipulates that the villagers, local Sangha, a local administrative head should meet together to decide. This is still followed in Thailand. No doubt practice varies, but this is what happened in one Wat Pa Pong branch monastery that I was staying near in Nan, northern Thailand.
For your interest, here is the official text of all three Thai Sangha Acts.
Thai Sangha Act 1902
Article 8.
The authorities of the State are empowered to look after an abandoned monastery, that is to say, one in which there is no Bhikkhu, – together with its estate.
Article 9.
Anybody who wishes to build a new monastery is first to apply for Royal permissiom through the following manners:
(5 legal criteria)
In case of the unanimous approval on the part of the State District officer and the eccesiastical District Chief with reference to the five points mentioned above, the latter is authorized by Royal Permission to present the documents in order to be sealed by the former. The owner of the land is to transfer its ownership to the order of Sangha before any building process can be started.
Article 10.
There is to be an abbot for a monastery. (the King is to choose the abbot of royal monasteries, and may if he wishes appoint other abbots as well.)
Article 11.
(Otherwise, if in Bangkok) it shall be the duty of the Rājāgaṇa District Governor where the monastery is situated to summon a meeting of the Bhikkhus together with the lay devotees of that monastery for the sake of selecting the abbot. If the Rājāgaṇa District Governor has decided in favor of any bhikkhu, he (the former) is empowered to issue a certificate appointing the latter to be the abbot. The certificate of appointment shall also be counter-sealed by the Minister of Religious Affairs.
Article 12
(Slightly different procedure for monasteries outside of Bangkok)
Now all abbots, unless they have been already bestowed a higher Ecclesiastical title, shall bear the title of Adhikāra.
Article 18.
An appeal against the abbot’s order, in case it is a monastery in Bangkok, can be filed to the Rājāgaṇa District Chief; in case it is one on the province, can be filed to the Ecclesiastical District Chief.
Thai Sangha Act 2505
Article 32
Construction, establishment, combination, removal (from one place to another), abrogation, and applying for official recognition of consecrated boundaries (sīmā) shall conform to the ministerial regulations.
In case of abrogation, the property of the abrogated monastery shall be annexed to the Central Ecclesiastical property.
Article 33.
Land both belonging to a monastery and under control of a monastery is of the following categories:
- Monastery Compound. This means the area wherein various structures of a monastery are situated.
- Monastery Estate. This refers to a piece of land belonging to a monastery.
- Monastery revenue estate. This is a piece of land, the rent or other benefits of which is dedicated to the upkeep of a monastery or of the Buddhist order of Saṅgha as a whole.
Article 34.
Transference of ownership of the area wherin various structures of a monastery is situated or of a piece of land belonging to a monastery can be accomplished only through an Act. Nobody shall be allowed to file a case against a monastery by right of prescription concerning the property which is either a monastery compound or a monastery estate.
Article 35.
Monastery Compund and Monastery Estate are properties that are not subject to any enforcement by the Court of Law.
Article 36.
There shall be one abbot for a monastery. However, when it is deemed proper, there can be a vice-abbot or an abbot’s assistant.
Article 39.
In case of the absence of an abbot or his disability an acting abbot is to be appointed, with the same governing power and responsibilities as the abbot himself.
Appointment of an acting abbot is to conform to the principle and procedure determined in the rules of the Council of Elders.
Sujato’s Blog 
Hmm, Act 2505’s Art 33 is cute. Why distinguish a monastery compound from a monastery estate? What if the compound is larger than the estate?
I suppose Art 34 will then block claims for adverse possession if the compound encroaches on private estates.
My understanding is that legal documents take great care to define terms, which is why the distinction would be made. Perhaps in the case of a ‘squat’ the building may be owned by the Sangha while the ground is rented from another authority. In this sort of case, the compound is larger than the estate. I’d want to read the rest of the Acts and relevant case law before deciding if it was a distinction without a difference.
The monastery ‘estate’ is, it seems, land owned by the monastery but not occupied by monks; perhaps vacant land. I have just corrected a mistake in the original post; there is supposed to be a third type of land, which I had mistakenly placed elsewhere, ‘monastery revenue estate’.
Article 34 refers to a right of prescription:
“Phillip Packer drives across the corner of Ralph Roundup’s ranch to reach Packer’s barn regularly for a period of ten years; for a decade Ralph Retailer uses the alley back of Marjorie Howard’s house to reach his storeroom. In each case the result is a “prescriptive easement” for that specific use. It effectively gives the user an easement for use but not ownership of the property.”
http://legal-dictionary.thefreedictionary.com/prescription
So, Article 34 seems to be offering a protection against having infrastructure or other interpolations on the land being used to shave monastery property into the hands of developers as a matter of course.
That this is found only in the most recent Act tells me this is an artifact of relatively recent case law, the particulars of which are surely revealing.
Dear David
Doubtless a correct analysis under Anglo-Saxon Common Law, but not necessarily the case with continental Civil Law. Modern Thailand borrowed the bulk of its jurisprudence from Germany, where “prescription” is equivalent to the Common Law notion of “adverse possession”.
Dear Bhante
Was the translation yours?
Thanks for clarifying the distinction. At least that allowance will permit siima boundaries to be gifted by a larger envelope of aranna. But one wonders if loggers and poachers respect the leal integrity of such Monastery Estates any longer?