The nature of OSB Plywood makes it water resistant. The best OSB is created by compressing and gluing wood flakes together to form strong, durable surfaces.
Plywood & OSB
OSB Sealer
OSB Substrate Compatibility With Waterproofing Systems - Pli-Dek
Is OSB Plywood Water Resistant? - Silvaris
Oriented Strand Board (OSB) - APA – The Engineered Wood Association
What is OSB Sheathing Used For? - Silvaris
How Does OSB Compare to Plywood - Silvaris
Amdry 1.6 in. x 2 ft. x 4 ft. R5 OSB Insulated Subfloor Panel AMD0140G - The Home Depot
OSB Board, Plywood Sheets & B-Grade Lumber - Silvaris Corporation
Are OSB Panels a Sustainable Resource - Silvaris
OSB vs. Plywood: Which is Better? - The Craftsman Blog
OSB 6/9/12mm for OSB Plywood/Waterproof OSB for Roof Sheathing/OSB Board - China Furniture, Building Material
What is OSB Sheathing Used For? - Silvaris