MapGrid aggregates publicly available government geospatial data. All source data remains the property of the issuing agency. This page documents every data source, its provider, verified licensing terms, and any restrictions.
Last audited: May 2026. Licensing research conducted via direct inspection of each state's GIS portal terms of use pages. Policy URLs linked where available.
Legal Basis for Federal Data
Federal government data is in the public domain under 17 U.S.C. §105 and the OPEN Government Data Act (2019, 44 U.S.C. §3502). State data varies — each state's terms are documented individually below.
Data from the following states is used under Creative Commons Attribution 4.0 (CC BY 4.0): Utah (UGRC SGID), Colorado (State of Colorado), Oklahoma, South Dakota.
Data from the following states is used under Creative Commons Attribution-ShareAlike 4.0 (CC BY-SA 4.0): Michigan, Washington, Rhode Island (RIGIS), Vermont (VCGI), Wyoming, Tennessee, Florida (DEP), Missouri (MSDIS), Alabama.
All state and federal source data has been modified from its original form. Changes include: field name mapping, coordinate system reprojection to WGS 84 (EPSG:4326), geometry format conversion (Esri JSON to GeoJSON/PostGIS), and integration into a unified multi-state database schema. Data is refreshed on scheduled intervals and may not reflect the most current version available from the source agency.
Data originating from CC-BY-SA licensed sources and served through the MapGrid API retains its CC-BY-SA license. Users who download or export data from CC-BY-SA states must comply with the CC BY-SA 4.0 terms, including attributing the source agency and licensing any redistributed derivative data under CC-BY-SA 4.0.
All federal data is public domain per 17 U.S.C. §105. No restrictions on commercial use. Attribution not legally required but provided as best practice.
| Dataset | Agency | Attribution |
|---|---|---|
| FEMA Flood Zones (NFHL) | FEMA | Source: FEMA National Flood Hazard Layer |
| Superfund (NPL) Sites | EPA | Source: U.S. EPA Facility Registry Service |
| Brownfield Sites | EPA | Source: U.S. EPA Facility Registry Service |
| RCRA Regulated Facilities | EPA | Source: U.S. EPA Facility Registry Service |
| Toxics Release Inventory (TRI) | EPA | Source: U.S. EPA Facility Registry Service |
| National Wetlands Inventory (NWI) | USFWS | Source: U.S. Fish & Wildlife Service |
| Opportunity Zones | Treasury / CDFI Fund | Source: U.S. Department of the Treasury |
| Satellite Imagery (Basemap) | USGS | Source: USGS The National Map |
These states have terms that may restrict commercial use. Data from these states requires written authorization, has explicit non-commercial clauses, or carries copyright claims that prevent unrestricted reuse.
Commercial use prohibited without written agreement
eHawaii ToU: "You agree not to use for commercial purposes... unless allowed in a separate, written agreement"
"Personal and non-commercial use" only (data.nebraska.gov)
NebraskaMap.gov (GIS portal) is separate and less restrictive, but no explicit commercial license
Commercial use prohibited without written permission + possible license fee
ISGS is part of University of Illinois; copyright held by Board of Trustees
"Authorized users only, approved business purposes" (ArcGIS portal)
Portal includes restrictive language; old imap.maryland.gov is defunct (404). Contact [email protected]
Historically restricted resale of raw data
MassGIS Terms historically permitted derived products but restricted raw data redistribution. Site returned 403. Contact [email protected]
"All Rights Reserved" copyright notice on portal
Footer reads "Arkansas GIS Office. All Rights Reserved." No open data license found
"Copyright 2015 Earth Data Analysis Center, UNM"
University-operated clearinghouse claims standard copyright. Contact [email protected]
Varies by provider — some counties explicitly prohibit commercial redistribution
PASDA is a clearinghouse with 200+ providers. Lancaster County prohibits redistribution. Verify per dataset
State imagery restricted to government use only (Google license)
OCGA 50-29-2 authorizes GIS data sales. Non-imagery data: contact GIO. Do NOT use GA imagery commercially
SCDNR "retains all rights"; court precedent supports licensing restrictions
Seago v. Horry County supports GIS licensing restrictions. SCDNR claims all rights. Contact [email protected]
ARS 39-121.03 — commercial use OK but must disclose purpose + may owe fees
Unique: commercial purpose must be disclosed in writing. Market-value fees may apply. Treble damages for non-disclosure
No license; Parcel Data Exchange Standard exists but not publicly accessible
County-level data sharing agreements may impose restrictions. Contact Idaho Geospatial Office (IGO)
State copyright asserted ("Copyright 2019 State of Mississippi"); licenseInfo null
MARIS describes data as "FREE" but terms doc not publicly retrievable. Contact [email protected]
WVGISTC: "All Rights Reserved"; MapWV: permissive but ambiguous
WVGISTC asserts full copyright. MapWV allows "view, copy, distribute without obligation" but commercial use unclear
Custom "Data Distribution Agreement" — commercial use not explicitly permitted
Attribution required. Metadata must remain intact. Cannot imply sponsor approval. More restrictive than most states
KRS 61.874 — commercial use must be declared; misrepresentation is unlawful
Must certify commercial intent and pay commercial-rate fees. KYTC data is CC0. Non-KYTC data needs formal agreement
KSA 45-220(c)(2) — certain records require no-commercial-use certification
Whether parcel GIS data falls under certification requirement is unconfirmed. Contact DASC at kansasgis.org
| State | License | Agency | Policy |
|---|---|---|---|
| New Jersey | NJ Open Data — "anyone may view, copy or distribute without obligation" | NJDEP / NJGIN | Link |
| Texas | Public domain — "content is considered public domain" — Attribution appreciated but not required | TCEQ | Link |
| North Carolina | "Free and unrestricted use" — no written release required — Portal metadata also references CC-BY-SA | NCDEQ / NC OneMap | Link |
| Utah | CC BY 4.0 — Must credit "UGRC SGID" and include last-updated date | UGRC | Link |
| Colorado | CC BY 4.0 — Must credit "State of Colorado" | CO OIT GIS | Link |
| Oklahoma | CC BY (data.ok.gov) — GIS portal (okmaps.gov) was unreachable; data.ok.gov uses CC BY for 66+ datasets | OK GIS | Link |
| New York | Custom permissive license (EO 95, 2013) — "use it as you wish" — No attribution required. Not CC but equivalently permissive. "No restrictions on use" per EO 95 | NY ITS / DEC | Link |
| Connecticut | CC0 (parcels confirmed); other layers vary — CT parcel layer is CC0 (public domain). Other DEEP layers may have null license — verify individually | CT DEEP / Geodata Portal | Link |
| California | CC0 required by state policy (SAM 5160.1) — State Admin Manual mandates CC0 or equivalent for published data. CA Supreme Court confirmed GIS is public record | CA Open Data Portal / DTSC | Link |
| Delaware | "Freely available for any purpose" (Open Data Council definition) — Open Data Council explicitly states data can be used for any purpose. No attribution required | FirstMap / Open Data Council | Link |
| Oregon | ORS 276A.356 — statute prohibits use restrictions on published data — Statutory mandate: "without restrictions on use." Individual agencies may opt out under ORS 276A.509 | OR GEO / DEQ | Link |
| Virginia | VA FOIA (§2.2-3704) — no restriction on use of public records — FOIA "does not restrict how public records can be used once obtained." Attribution to VGIN recommended | VGIN / VDEQ | Link |
| Ohio | OH Public Records Act (ORC §149.43) — no commercial use restriction — No purpose-of-use condition except for BMV/student records. Verify individual county dataset metadata | OGRIP / OH EPA | Link |
| Nevada | NRS 239.010 — no commercial restriction; NRS 239.054 allows cost-recovery fees for GIS only — Public records law broadly permits use. GIS statute allows fee recovery but no use restriction. Parcel data is county-managed | NV GIS | Link |
| Montana | MT public records law — "no restriction placed on subsequent use of information provided" — MSL content is public domain. MCA mailing-list restriction (§2-6-109) does not apply to GIS display | MT State Library / DOR | Link |
| North Dakota | Open records law — no restrictions on use of records — ND sunshine law places no restrictions on use including commercial. No formal license but low risk | ND GIS Hub | Link |
| South Dakota | CC BY (confirmed via data.gov catalog) — CC-BY license documented in federal open data catalog. Attribution required | SD BIT | Link |
| Maine | Board policy explicitly permits commercial products — "No restrictions will be placed on re-use... may be used to create derivative data or commercial products" | Maine GeoLibrary | Link |
| Alaska | Public domain default ("datasets on data.Alaska.gov are in the public domain") — AK open data definition prohibits non-commercial restrictions. ADF&G wildlife data excluded (needs consent) | AK DEC / DCCED | Link |
| Iowa | CC0 1.0 (Iowa DOT GIS data) — DOT GIS data is CC0 public domain. Non-DOT data has no stated license — verify individually | Iowa DOT GIS / DNR | Link |
| Indiana | Public records — IC 4-23-7.3 ("not subject to licensing or royalties") — State GIS law establishes public access without royalties. No formal CC license but statute supports commercial use | IndianaMap / IDEM | Link |
| Minnesota | MN Data Practices Act — "does not restrict in any way the use of government data" — Metro counties adopted open data resolutions (2014-15). Statewide dataset contains opt-in counties | MN Geospatial Commons / MPCA | Link |
| Wisconsin | Public domain — SCO explicitly states "no use restrictions" — Statewide parcel data is public domain per SCO. WI Stat. §19.35 prohibits denying requests based on commercial purpose | WI State Cartographer / DNR | Link |
| State | License | Agency | Policy |
|---|---|---|---|
| Florida | CC-BY-SA + FL Sunshine Law (Ch. 119 F.S.) — Sunshine Law permits commercial reuse of public records; DEP portal metadata shows CC-BY-SA | FL DEP | Link |
| Michigan | CC-BY-SA — Attribution required; derivative works must carry same license | MI State GIS / EGLE | Link |
| Washington | CC-BY-SA — ShareAlike applies to derivative works | WA Geospatial / Ecology | Link |
| Rhode Island | CC-BY-SA 4.0 — Must credit "RIGIS"; derivative products must use CC-BY-SA | RIGIS | Link |
| Vermont | Custom policy + CC-BY-SA in metadata — Value-add commercial use OK; direct resale of unmodified data prohibited | VCGI / VT ANR | Link |
| Wyoming | CC-BY-SA 4.0 — Wyoming Geospatial Hub metadata confirms CC-BY-SA. Attribution required | WY Geospatial Hub (WyGISC) | Link |
| Tennessee | CC-BY-SA — geodata.tn.gov uses CC-BY-SA. Attribution required; derivatives must use same license | TN GIS / TDEC | Link |
| Missouri | CC-BY-SA (confirmed on MSDIS open data portal) — MO Sunshine Law has no commercial restriction. CC-BY-SA share-alike applies to derivative distributions | MSDIS (U of MO) / MO DNR | Link |
| Alabama | CC-BY-SA (confirmed on AL Open Data Portal) — AL §36-12-40 makes no distinction for commercial use. CC-BY-SA share-alike applies to derivative distributions | ALDOT / ADEM / AGIO | Link |
These states publish data on public GIS portals but have no discoverable open data license. Data is treated as public government records under each state's Freedom of Information / public records law.
| State | Status | Agency | Policy |
|---|---|---|---|
| New Hampshire | No explicit license (university-operated) — UNH IP policies may apply separately from state records law. Contact [email protected] | NH GRANIT (UNH) | Link |
Tax sale listings are aggregated from publicly posted legal notices on county and municipal government websites. These are public records required by law to be published for public notice. 274 scraper configurations cover all 50 states + DC.
Legal basis: Feist Publications v. Rural Telephone Service (1991) — raw factual data (property addresses, amounts, dates) cannot be copyrighted. Post-Van Buren v. United States (2021), accessing publicly available websites does not violate the CFAA.
| Basemap | Provider | License |
|---|---|---|
| Street Map | OpenFreeMap | Open source (free for all use) |
| Topographic Map | OpenFreeMap | Open source (free for all use) |
| Dark Map | CARTO | CARTO free tier (commercial use allowed) |
| Satellite Imagery | U.S. Geological Survey (USGS) | Public domain (17 U.S.C. §105) |
Disclaimer: MapGrid is not authorized by, endorsed by, or affiliated with any government agency listed above. Data is provided for informational purposes only. See our full data disclaimer.