Article III: On Accession

I. Notions. 1. Accession is a certain increase of one's own thing, arising from the fact that another thing, not one's own, is joined to it, accedes to it (Cf. Ital. Code art. 443). - When that joining extends ownership, accession becomes a mode of acquiring, which nevertheless is easily reduced to occupation. This, however, happens both by nature and by positive law.

This acquisition is governed by a twofold principle: "a thing bears fruit for its owner"; that is, what a thing produces is of itself possessed together with the thing itself; and "the accessory follows the principal." The former principle is demonstrated by the law of nature itself, at least when no labor of another or thing of another has cooperated in the fructification, or, if there has been some cooperation, this has been compensated by a price; but the other principle rather supplies a reason for positive sanctions of laws. For of itself, the conjunction of an accessory thing with the principal would induce a certain co-ownership.

2. Accession, however, is distinguished as accession common to movable and immovable things; accession proper to movables; and accession which has place only in immovable things.

a) Accession common to movable and immovable things occurs by birth. "A thing bears fruit for the owner" of the fruit-bearing thing. The offspring of an animal belongs to the possessor of the one giving birth (and therefore of the female): "the offspring follows the womb." Likewise the fruits which nature alone, or the industry of men, or both causes together have produced, for example the fruits of a field, of a tree, etc., are assigned to the owner.

b) Accession proper to movables occurs either by simple joining, as when a gem is inserted into a necklace; or by specification, when the juridical species of a thing is changed, with some industry presupposed, as when a statue is made from marble; or by commixture (which is called confusion when liquids are in question), when several things are mixed in such a way that whose bodies are whose can no longer be discerned: as if two stores of wheat, or two wines, are mixed.

If these things have been done by common consent, attention must be given to the contract. Otherwise, they are governed by equity, which laws attempt to interpret for various cases, using this principle: "accession yields to the principal" (L. 19, § 13, 1). De auro, argento, XXXIV, 2).

c) Accession proper to immovables occurs by alluvion or by reliction, when waters either, little by little and imperceptibly, bring a hidden increase to a field; or recede gradually; or by an island formed (in the middle of the riverbed); or by a changed bed of a river; or by building, when a building is constructed with another's material, or is placed on another's soil; or by planting, when someone has planted certain things in another's ownership. Here too this holds: "It is fitting that the accessory follow the nature of the principal" (Reg. 42 Iur. in 6). But jurists must be approached.

d) But metallic veins, quarries, and sand-pits are governed by special laws for the common good. Nothing strictly prevents the State from claiming for itself the monopoly of exploiting them; but that this will yield to the common utility is rightly doubted. Similar things can be established concerning certain springs, for example petroleum-bearing ones, which begin to flow in some field.

R. P. Slater, p. 375, gives these examples of accession. The owner of a field acquires increases effected by alluvion; an island which appears in a river belongs to the owner of the riverbed. But if a river suddenly changes its bed, ownerships remain intact.

One who has built a house with another's wood acquires the wood, but must indemnify the owner. A painter becomes the owner of the canvas on which he has exercised his art, but he will have to repay the price of the canvas. By the introduction of a new form, as if you make bread, wine, or oil, the ownership of the thing effected will belong to the artisan, who will have to pay the price of the material. If liquid or solid things of several owners have been mixed, of themselves they must be separated; if this cannot be done, each obtains a right in the price of the thing in proportion.

5. You ask whether possession of the soil of itself grants a right to the things which are above or below? This is by no means effected by natural law; for by the same limits by which the kind of occupation is circumscribed, the very right of property itself is circumscribed.

But it happens that positive laws, for example the Italian Code art. 440; French art. 552, assign also the things which are above and below (le trefonds) to him who possesses the soil.

Positive Laws. 1. Concerning Latin law, after what has been said, nothing in particular is to be observed.

By Canadian law Q., for a sudden change of riverbed, rivers which are not in the ownership of private persons (those which can serve ships or the transporting of logs: flottables et navigables) are distinguished from others. In the former case, the abandoned riverbed belongs to the State; in the latter, to those who possess the fields invaded by the river. - Nor does the bad faith of the one effecting accession impede the transfer of ownership.

2. By German law these things are established. Fruits and things which are part of a thing belong to the owner of that thing even after separation (art. 953). Movable things which become one thing with an immovable thing in such a way that they are essential to it yield to the owner of the immovable thing. By the union of several movable things, co-ownership of several persons is effected, unless one thing is more principal. One who by his labor has introduced a new juridical species acquires the thing, unless the material was much more precious. But when the right of perfect ownership is extinguished, other rights in the thing are at the same time extinguished. But those who have been injured can demand compensation. Concerning alluvion, an island, etc., the various laws of the States must be consulted.

3. Concerning the law of England, observe this: by more recent statutes, which confirm the older custom, compensation for useful expenses is owed to him who withdraws from a house or field.

4. In the U.S.A., artificial accession does not change rights if it has been carried out without good faith. Moreover, the whole thing confused or commixed is assigned to him toward whom the one mixing was injurious. But before the sentence of a judge, one can stand by natural law. Cf. Garepy, n. 1506.

Concerning the obligation of conscience it will be enough to advise this: those laws, insofar as they at least supply the silence of natural law, or are applied by the sentence of a judge to the juridical relations of the parties, bind conscience.