In continental jurisdictions a work is only protected insofar as it reflects an own personal creation. Joint Ownership will exist if a protected work has been created by two or more persons. Joint ownership, in this sense, equates to joint authorship. Under continental authors rights, an assignment of copyright so as to create a new copyright is not permissible. Typically, the author will only be able to assign the economic rights, in whole or part. Moral rights will remain with the original authors.

The general requirement for joint ownership to subsist is that a work has been created by at least two persons. The term creation refers to a contribution displaying at least a level of originality in the sense of an "own personal creation". Mere laborious efforts do not suffice. The second requirement for true joint Ownership to subsist is that each contribution becomes an inseparable element of the work, i.e. the result of such contribution cannot be commercially exploited in its own right.

The first requirement would exclude not merely contributions not reaching the required of originality, but also the provision of mere mechanical assistance and the sheer provision of ideas and information. The second requirement for joint Ownership to subsist is that the contribution is indistinguishable from the other contributions; in short, if the individual contribution would commercially be exploitable, there would simply be separate work. For example, authors whose poems have been included in an anthology thereby do not become joint Owners as their works remain separable with respect to the anthology. In the same way, works which are merely loosely connected cannot yield joint Ownership if they are types of different creations, such as the lyrics and the melody to a song. Here, both works are protected in their own right without melting into one overriding copyright. The effect is that each author will require a licence.

The situation under UK copyright law (and also US law) is less clear as to the necessary contribution to yield joint ownership. Whereas it is undisputed that the rules relating to the separation of contributions will equally apply, the necessary level of contributory originality is less clear as UK copyright law protects skill and labour. It is therefore capable to render any, possibly even mechanical contributions into some protected augmentation. However, the sheer concoction of assistance or provision of ideas will likewise not create Joint Ownership

Initial ownership is partially regulated with respect to works uniting various copyrighted works underneath the level of direct fixation, such as in the case of films (attributed to either producer or director) or certain types of collective works (such as anthologies, recipe books, catalogues) in which the editor is granted first copyright in the selection and arrangement of materials, not in the individual works itself).

True Joint Ownership therefore only exists where, for example, two or more parties have contributed in such a way that no distinguishable contribution subsists. The effect is that any dealing remains subject to the other parties consent. However, various copyright statutes will provide that one joint owner may not exercise his right to not exploit the work without some essential justification.

A work of Joint Ownership will, by operation of the law , create an undivided share for each joint owner, i.e. the interest in the intellectual property will be shared equally. It is therefore not possible to make a distinction with relation to the possibly unequal quality of creative contribution.

Under German law, and possibly most continental laws, the effect of Joint Ownership is, in the absence of any agreement to the contrary, to create a legal entity sharing undivided interests in the intellectual property right - i.e. each party holds a nominal equal share, divided simply per head ( Bruchteilsgemeinschaft). Such result is not desirable as it is fraught with difficulties.

The main principles are:

• Each joint owner can assign his interest to a third party, this party will then replace the former joint owner with respect to the interest.
  
  
• Any dealing in the work is subject to consent.
  
  
• In the case of one parties' death his interest will pass to the others.
  
  
• In the case of the insolvency of one joint owner, his interest can be transferred to creditors.
  
  

Under UK copyright law, the situation is, again, dubious. Much depends on whether the situation is commercial in nature, i.e. if an underlying and initial will to commercially exploit the asset can be detected (see c) below).

In theory, English law draws a distinction as between joint tenancies and tenancies in common. Both are sub-divisions of the term joint ownership. The expressions stem from land law but are applied to Intellectual Property rights likewise. In practice, the distinction is that in the case of joint tenancy each tenant has a right of survivorship. If one owner dies (or, in the case of a body corporate, the body is dissolved) his share passes equally to the others, so that their share is equally increased. In the case of tenancy in common, the share passes with the estate, i.e. it can be inherited.

Both terms, however, refer to a right in undivided shares - each joint owner, irrespective of the quality of his particular contribution, holds a proportionate share.

In both systems, the possible intention of the parties is important. If there is a will to commercially exploit the work, continental legal systems will then consider the relationship as one between directors of a company with unlimited liability by capital (under German law, for example, a Gesellschaft buergerlichen Rechts or civil partnership). The implied intention here will create an assumption that all joint owners intended to from a company. They will, in that sense, become directors of a company in the form of a civil partnership under the Civil Code. Consequentially, the general rules pertaining to vote rights in civil partnerships are applicable, although courts have rejected claims for an increase in majority voting even though the contributions had been unequal. In effect, this denotes that shares may pass on with the estate only if agreements to the contrary - which can be implicit - are absent. Under UK copyright law, the intention to commercially exploit the work in general allows for an assumption as to a tenancy in common.

Important modifications are made in the case of employee works. In particular, the European software directive provided for the employers right to the commercial benefits. A similar provision allowing the transfer of a license to exploit to the employer can be found in most copyright statutes. This means that the employer does not automatically become owner. The employee is obliged, though, to transfer any rights. Such transfer is not to be understood too technically. For each work created, the employer will become an exclusive licensee even without any express transfer. The employer does not become owner of the copyrighted work but is merely permitted to exploit the work.

A similar situation to the employee works exists in the case of commissioned works. As copyright exists without registration, the right will vest in the author despite the fact that it was made for specific purposes or following the instructions of the commissioner. Here, UK copyright would give the commissioner an equitable title to use the work. In theory, the author remains owner. However, the commissioner may claim from the author to have the right transferred. Against third parties, the commissioner will then be treated like the legal owner.

Under continental laws, the result is largely similar, as an implied consent will exist which allows the commissioner to use the work in accordance with the parties' intention.