Not as a derivative. L-2 status is available to a spouse in a legally recognized marriage and to unmarried children under twenty-one, and a common-law relationship recognized in Ontario does not create a spouse for this purpose. A partner in that position needs an independent basis to enter and remain.
The definition of spouse is the one that governs, not the one at home
This surprises people, because provincial law treats a long common-law relationship as equivalent for many purposes. Federal immigration law does not, and the practical result is that a partner would have to look at a visitor route with all its limits, a status based on their own study or employment, or marriage. Each of those has consequences worth thinking through before anyone resigns a job.
A visitor cannot work, and repeated long stays attract questions. A student route requires an accepted program and proof of funding. Where the partner has their own profession or an employer with an American entity, their own route may be simpler than the derivative one would have been.
For couples who do marry, the derivative status carries a genuine benefit: an L-2 spouse is employment-authorized incident to status and may work for any employer.
- USCIS: L-1B Intracompany Transferee Specialized Knowledge
- USCIS Policy Manual: L-1 nonimmigrant classification
- 8 U.S.C. 1184(c)(2): L-1B placement at a third-party worksite
- eCFR: 8 CFR 214.2(l), Intracompany transferees
- USCIS Policy Manual: employment authorization for certain spouses
- USCIS: Form G-1055, Fee Schedule