Short answer. Nearly anything within the commerce of man can be left as a legacy. Article 924 provides that all things and rights within the commerce of man may be bequeathed or devised, so beyond land and money this reaches movable property, credits, shares, usufructs, and other transferable rights the law allows a person to own.
What the law says
All things and rights which are within the commerce of man be bequeathed or devised.
Civil Code, Article 924 — What May Be Given by Legacy or Devise. Read the full provision →
The general rule: almost anything transferable
Article 924 sets the boundary as widely as possible: what may be left as a legacy or devise is anything within the commerce of man — meaning anything that can lawfully be owned, sold, or transferred between people. The rule is not a fixed list of approved categories; it works the other way around, ruling out only what the law keeps outside ordinary commerce, such as things that cannot be privately owned at all, or rights the law makes strictly personal and non-transferable. Everything else can, in principle, be the subject of a testamentary gift.
What this reaches beyond land and money
Read broadly, the article covers movable property of every kind — vehicles, jewelry, furniture, livestock, and personal belongings — as well as intangible rights such as credits owed to the testator, shares in a corporation, a usufruct or other real right the testator holds over someone else's property, and even an interest in a business or partnership, so long as the right itself is something the testator could have sold or assigned during his lifetime.
The limit built into the phrase 'within the commerce of man'
The qualifying phrase does real work: rights that the law forbids from being bought, sold, or transferred at all — because they are personal to the holder, or because public policy keeps them outside ordinary trade — fall outside Article 924's reach, even if the testator wanted to leave them to someone. The test is whether the thing or right could, in principle, be the subject of an ordinary transfer between living persons; if it could, it can generally be left as a legacy or devise as well.
How the identification actually works in a will
A will still has to identify the thing or right clearly enough for the executor and heirs to know what is being given, and the general rules on legacies elsewhere in the Code govern how a specific item is to be delivered once it is identified. Article 924's role is only to confirm that the category of the gift — whether jewelry, a receivable, a share of stock, or a right of usufruct — is not, by its nature, barred from being left this way.