Unless you have agreed otherwise, each co-owner may exploit the invention themselves, regardless of the size of their share. A licence to a third party may be granted only with the consent of all co-owners, in Slovakia as well as in Czechia. Because the statutory rules favour whoever has the manufacturing capacity, exploitation, licences, fees and exit from the project belong in the agreement between the partners.
Joint development often ends in a joint patent application. Both companies are then recorded as co-owners, and at first that feels fair. The problem shows up later, when one side starts manufacturing the invention at scale and the other, which has no production of its own, would like to license it to someone else. The statute has an answer for that situation, and it may not be the one you had in mind when signing.
Anyone may exploit, only everyone together may license
In Slovakia, the co-owners’ shares derive from the extent to which the right to the technical solution belongs to them, unless they agree otherwise (Section 20(1) of Act No. 435/2001 Z. z.). For exploitation itself, however, the size of the share is irrelevant:
Each co-owner of a patent has the right to exploit the invention that is the subject of the patent, unless the co-owners of the patent agree otherwise.
— Section 20(3) of Act No. 435/2001 Z. z. (unofficial English translation)
A co-owner with a ten per cent share may therefore manufacture to the same extent as one with ninety, and the Patents Act does not expressly require them to pay the others for that exploitation. Whether, and how, the rules on co-ownership in shares apply mutatis mutandis here is a question it is safer to resolve by contract than by litigation. Licensing is the opposite. Granting a third party the right to exploit the invention requires the consent of all co-owners, unless they agree otherwise (Section 20(4)). The side without production therefore needs, for a third-party licence, the consent of a partner who is often its competitor.
Where the patent is infringed, each co-owner may sue alone; a decision given on one co-owner’s action is, however, binding on the others as well (Section 20(3)). Other relations between co-owners are governed mutatis mutandis by the Civil Code rules on co-ownership in shares (Section 20(8)). An agreement dissolving the co-ownership and settling it must be in writing and takes effect against third persons only on entry in the register (Section 20(5)). A partial transfer of a patent is not permissible (Section 21(1)); a co-owner may nonetheless dispose of their co-ownership share, as Section 20(4) recognises by its reference to Sections 21 to 23. Whether the other co-owners have a pre-emption right on a transfer of a share under the rules on co-ownership in shares is not expressly regulated by Slovak law.
How Czech law deals with it
Czech Act No. 527/1990 Sb. rests on the same basis. Unless the co-owners agree otherwise, each of them may exploit the invention, and a licence agreement requires the consent of all (Sections 16(2) and (3)). It additionally regulates transfers expressly: transferring the whole patent requires the consent of all, and a co-owner may transfer their share to a third party only if no co-owner accepts it within one month of a written offer (Section 16(4)). In a Czech-Slovak project with patents in both countries, it is therefore necessary to allow for the rules on transferring a share differing between them.
What to agree in the cooperation agreement
The statutory rules are non-mandatory, so you may replace them by contract. A research and development agreement, or a separate co-owners’ agreement, should cover:
- who may exploit the invention, in which field and in which territory,
- whether, and what, a co-owner exploiting the invention alone pays the others,
- how decisions on third-party licences are taken and whether one party may grant a licence alone,
- who pays the maintenance fees and what happens to the share of a party that stops paying,
- who conducts litigation over infringement and how the costs and proceeds are divided,
- a pre-emption right or another mechanism for a party leaving the project.
These questions are far easier to resolve before the application is filed than at the point where one side is already manufacturing. We prepare an agreement allocating rights to results, licences and rules for co-ownership through research and development collaboration agreements. If you are working with a competitor, see also our article on joint development and the EU block exemption.
This answer provides general information on the law as at 12 September 2026. It does not constitute legal services or replace an assessment of an individual case. The details of your situation may differ. Book a consultation to discuss them.
