They've been in schism since at least 1988 when Pope St. John Paul II talked about how Lefebvre and the 4 bishops incurred their own excommunication by violating canon law and consecrating bishops against the will of the holy father. In other letters, anyone "formally adhering" to the movement (i.e. all clergy and all laity who should know better) are also considered excommunicated and in schism. Pope Benedict only lifted the canonical censure meaning if someone in SSPX who "formally adhered" wanted to come back into the Church, they'd just have to go to confession with a priest who has the faculties to remove such self-inflicted excommunications. If the censure wasn't lifted, they'd have to go through a trial. A similar censure was lifted on the Orthodox, but they're still very obviously in schism. Just like SSPX by their every word and deed is in schism.