The not in force since date is the date on which the rights conferred by the patent are no longer considered to be in force. The not in force since date may or may not be the same as the invalidation date.
Patent expired: patent expired after 20 years, i.e. on the day of the anniversary of the filing date of an application. Thus a 20 years period that starts for example on 10 January 2000. ends on 10 January 2020.
Patent lapsed(date of the last fee payment): patent lapsed due tonon-payment of an annual fee (e.g. HRP20150166 / EP2574226).
Patent surrendered: patent no longer valid due to a written declaration of the holder of a patent on the surrender of its rights; it takes effect on the day following the day of its submission to the SIPO HR. Annual fees could have been paid before the request for surrender was submitted (e.g. HRP20120960 / EP2121139).
Patent revoked: Validated patent declared null and void by the EPO or SIPO HR; revocation has a retro-active effect to the filing date of a European application (e.g. HRP20120790 / EP2185191).
Since revoked patents are patents that are no longer in force, both “Invalidation Date” and “Not in force since” Date in Federated Register are displayed.
“Invalidation Date” is the date of the legal effect of the decision on revocation of a European patent either before the EPO, or before the SIPO Croatia (when the decision on the invalidation was taken).
“Not in force since” date is the filing date of a European application, since the effect of revocation, according to the Croatian Law, is ex nunc.
The "not in force since" date could also be retroactive to the "invalidation date", the date on which the legal obligation was not filled, e.g. renewal fees were not paid, invalidation occurs after expiry of time limits, but patent only in force until end of period for which the fees were paid.
Annual fees could have been paid before the request for revocation was even filed or after the decision related to the opposition was made. If so, the last annual fee paid will be displayed for that patent, although it is of no impact to the revocation.
“Record last updated” is unrelated with the “Not in force” date.