Q: What halachic liability is entailed in copying a program or disc for private use?

A: According to the opinion that halacha recognizes ownership of intellectual property, some write that there is a prohibition of "theft" (gezel) in copying. (Igros Moshe O.C. 40:19) However, the Rambam (Hil. Shofar 1:3) indicates that actual theft does not apply to something intangible.

There is an ancillary prohibition, though, to benefit (neheneh) from another's property against his will, which applies also to something intangible.

As such, if the person might have bought the program or disc, he is liable on the basis of "zeh neheneh v'zeh choser." He might not be liable for the full cost, though, since the copied item lacks technical support, user's manual, etc.

Even if the person would not consider buying the item, so that that the creator is not choser (losing), it is still prohibited to benefit against the owners will. However, if one did copy, he might not be liable, since he did not cause the owner a "loss."

Of course, dina d'malchusa and minhag hamedina would have to be considered.

(See Emek Hamishpat, Zechuyos Yotzrim, Intro. ch. 3; ch. 25-28)