This data set contains the Submerged Lands Act (SLA) boundary line (also known as State Seaward Boundary (SSB), or Fed State Boundary) in ESRI shapefile formats for the BOEM Atlantic Region. The SLA boundary defines the seaward limit of a state's submerged lands and the landward boundary of federally managed OCS lands. In the BOEM Atlantic Region it is projected 3 nautical miles offshore from the baseline. Further information on the SLA and development of this line from baseline points can be found in OCS Report MMS 99-0006: Boundary Development on the Outer Continental Shelf https://www.boem.gov/BOEM-Newsroom/Library/Publications/1999/99-0006-pdf.aspx. Due to slight differences in process and purpose, NOAA's 3 nautical mile line depicted on its charts may differ in some areas from the SLA boundary depicted on BOEM maps and OPDs and should not be confused with the SLA boundary. Therefore this boundary is the only boundary that should be used to depict state/federal seperation of jurisdiction for submerged lands. Because GIS projection and topology functions can change or generalize coordinates, these GIS files are onsidered to be approximate and are NOT an OFFICIAL record for the exact Submerged Lands Act Boundary. The Official Protraction Diagrams (OPDs) and Supplemental Official Block Diagrams (SOBDs) serve as the legal definition for offshore boundary coordinates and area descriptions.