First and Foremost
The answer lies within the fact that the Old Catholic Church did not LEAVE the unified Catholic Church. They were initially separated by the issue of persecution. Therefore there has never been a real issue over the validity of the Old Catholics or their relationship with the Catholic Church.
Secondly
There have been repeated affirmations by the Roman Catholic Church though the Papacy and other governing bodies. Some of which are listed here.
Historical Affirmations Regarding our Validity by The Vatican
1145 A.D.
Utrecht receives Rights of Autonomy from Blessed Pope Eugene III
1215 A.D.
This Right is confirmed by Pope Leo and becomes known universally as the Leonine Privilege
1520 and 1717 A.D.
Privilege subsequently reconfirmed in two Church Councils.
Most Recent Affirmations
Historical Affirmations Regarding Our Validity by The Vatican
From the pages of romereports.com
In an effort to strengthen unity among Christians, Pope Francis welcomed a delegation of the Bishops Conference of the Union of Utrecht, also known as ‘Old Catholics.’
”It has been possible to build new bridges of a more profound mutual understanding and practical co-operation. Convergences and consensus have been found, and differences have been better identified and set in new contexts.
Pope Francis
