According to R. 142(1)(b) EPC (R. 90(1)(b) EPC 1973) proceedings before the EPO shall be interrupted in the event of the applicant for a European patent, as a result of some action taken against his property, being prevented by legal reasons from continuing the proceedings before the EPO. An interruption under R. 142(1)(b) EPC serves the protection not only of the interests of the patent proprietor but also those of its creditors. This rule protects these interests by preventing any measure with legal effect from being taken, be it by the proprietor or the EPO, that is liable to adversely affect the patent's value as an asset (T 1389/18). For a case in which an opponent requested interruption of proceedings because of insolvency, see T 1533/07.

The decisive criterion for interruption under R. 142(1)(b) EPC is whether the action against the property was such as to make it legally impossible for the applicant to continue with the proceedings (J 26/95, J 16/05).

In T 854/12 the board held that R. 142(1)(b) EPC was applicable where a proprietor initially unrestricted in his procedural conduct was later "prevented from continuing the proceedings", but not where a patent was transferred with the administrator's consent to another proprietor who was already insolvent and therefore did not become a party to the proceedings but was instead represented from the outset by the administrator, whose powers of disposal were unlimited.

In J 9/90 the Legal Board held that for R. 90(1)(b) EPC 1973 to be applied in the light of Art. 60(3) EPC 1973 and R. 20(3) EPC 1973, the applicant entered in the Register of European Patents and the insolvent person (here a limited company) had to be legally identical. Cf. J 16/05.

In the cases J 9/94 and J 10/94, it was regarded as being analogous to a case of legal impossibility where the applicant, as a consequence of an action against his property, did not have at his disposal any remaining property by means of which he could have effected the required payment and he was thus, as a result of the action against his property, placed in a situation where it was factually and legally impossible for him to continue the proceedings before the EPO. In such a case it had, however, to be examined whether the actions taken effectively made it impossible for the applicant to continue the proceedings.

In J 18/12 the appellant company (applicant) had applied to the Legal Division for interruption of the proceedings, arguing that a court judgment had been issued – erroneously – against it, of which it had not been aware. This circumstance had only surfaced when it had applied for a bank loan, which had been refused due to its adverse credit rating, this latter being the direct consequence of the court judgment, which then directly resulted in its being left without any financial means. The Legal Board held that the correct interpretation of R. 142(1)(b) EPC required that there be a close relationship between the action taken against the property of the applicant and the condition that this action should be the cause of the applicant being prevented by legal reasons from continuing the proceedings. This requirement of causality would normally only be fulfilled if the "action" was a legal action and was directed against the property of the applicant as a whole, i.e. against the totality of the applicant's assets.

In J 26/95 (OJ 1999, 668) the Legal Board held that, in the absence of specific circumstances, proceedings against the applicant under Chapter 11 of the US Bankruptcy Code did not interrupt proceedings before the EPO within the meaning of R. 90(1)(b) EPC 1973 (R. 142(1)(b) EPC) (see also J 11/98). Being placed under Chapter 11 of the US Bankruptcy Code was an action taken against the property of the debtor. It did not, however, constitute a case where, as a result of such action, it was impossible for the debtor to continue the proceedings before the EPO. On the contrary, it was the very nature of proceedings under Chapter 11 that it was the debtor who continued to act for his business. Chapter 11 bankruptcy proceedings were therefore not comparable to the cases which had been recognised in the case law of the boards of appeal as leading to interruption of proceedings, i.e. where parties had been placed under receivership under French law (J 7/83, OJ 1984, 211) or been declared bankrupt under German law (J 9/90). A situation which could be compared to the exceptional case underlying decisions J 9/94 and J 10/94 (see above) had also not been substantiated.

In case J 11/95 the applicant had continued the proceedings before the EPO even after it had gone bankrupt. In particular, it had filed a request for entry into the regional phase before the EPO and paid the corresponding fees. The Legal Board held that from these facts and since no evidence to the contrary had been filed it had to be concluded that the applicant (in bankruptcy) was not prevented by legal reasons from continuing the proceedings before the EPO.

In J 16/05 the Legal Board held that R. 90 EPC 1973 did not provide for any time limit within which the circumstances establishing an interruption of proceedings would have to be brought to the attention of the EPO. The ratio legis of R. 90(1)(b) EPC 1973 was to protect parties not able to act in the proceedings for the defined legal reasons against a loss of rights which would otherwise occur, until such time as the EPO could resume the proceedings under R. 90(2) EPC 1973. The Legal Board also pointed out that in the interest of legal certainty, R. 90(1)(b) EPC could not be applied without any time restriction at all. Parties had to act in good faith and in due time and could not have an interruption of the proceedings established years after they had become aware of the facts justifying an earlier interruption.

In T 1389/18 the board held that the Legal Division generally had the power to establish that proceedings had been interrupted under R. 142(1)(b) EPC with retrospective effect too.