diff --git a/legal-api/src/legal_api/services/filings/validations/agm_location_change.py b/legal-api/src/legal_api/services/filings/validations/agm_location_change.py
index bb99f2c87a..bf3ea374a2 100644
--- a/legal-api/src/legal_api/services/filings/validations/agm_location_change.py
+++ b/legal-api/src/legal_api/services/filings/validations/agm_location_change.py
@@ -41,10 +41,16 @@ def validate(business: Business, filing: dict) -> Error | None:
     agm_year_path: Final = "/filing/agmLocationChange/year"
     year = get_int(filing, agm_year_path)
     if year:
-        expected_min = LegislationDatetime.now().year - 2
-        expected_max = LegislationDatetime.now().year + 1
+        current_year = LegislationDatetime.now().year
+        # AGM year can never be before the year the business was founded, even if that is
+        # more recent than the default 2-year lookback window.
+        founding_year = LegislationDatetime.as_legislation_timezone(business.founding_date).year \
+            if business.founding_date else current_year - 2
+        expected_min = max(current_year - 2, founding_year)
+        expected_max = current_year + 1
         if expected_min > year or year > expected_max:
-            msg.append({"error": "AGM year must be between -2 or +1 year from current year.", "path": agm_year_path})
+            msg.append({"error": f"AGM year must be between {expected_min} and {expected_max}.",
+                        "path": agm_year_path})
 
     # A non-empty reason (at least one non-whitespace character) is enforced by the schema
     # (business-schemas agm_location_change reason pattern).
diff --git a/legal-api/tests/unit/services/filings/validations/test_agm_location_change.py b/legal-api/tests/unit/services/filings/validations/test_agm_location_change.py
index 2793eeeb95..c08952b404 100644
--- a/legal-api/tests/unit/services/filings/validations/test_agm_location_change.py
+++ b/legal-api/tests/unit/services/filings/validations/test_agm_location_change.py
@@ -28,41 +28,48 @@
 # rejected by schema validation (HTTP 422) instead of the legal-api business check (HTTP 400).
 SCHEMA_REJECTED = 'SCHEMA_REJECTED'
 
+# Set far enough in the past that founding date never becomes the binding floor
+OLD_FOUNDING_DATE = datetime.utcnow().replace(year=datetime.utcnow().year - 10)
+
 
 @pytest.mark.parametrize(
     'test_name, expected_code, message',
     [
         ('INVALID_YEAR', HTTPStatus.UNPROCESSABLE_ENTITY, SCHEMA_REJECTED),
-        ('FAIL_YEAR-3', HTTPStatus.BAD_REQUEST, 'AGM year must be between -2 or +1 year from current year.'),
-        ('FAIL_YEAR+2', HTTPStatus.BAD_REQUEST, 'AGM year must be between -2 or +1 year from current year.'),
+        ('FAIL_YEAR-3', HTTPStatus.BAD_REQUEST, None),
+        ('FAIL_YEAR+2', HTTPStatus.BAD_REQUEST, None),
         ('SUCCESS-2', None, None),
         ('SUCCESS+1', None, None),
         ('SUCCESS', None, None)
     ]
 )
 def test_validate_agm_year(session, mocker, test_name, expected_code, message, monkeypatch):
-    """Assert validate agm year."""
+    """Assert validate agm year for an established business (founding date well outside the lookback window)."""
     monkeypatch.setattr(
         'legal_api.services.flags.value',
         lambda flag, default=None: "BC BEN CC ULC C CBEN CCC CUL"  if flag == 'supported-agm-location-change-entities' else default
     )
-    business = factory_business(identifier='BC1234567', entity_type='BC', founding_date=datetime.utcnow())
+    business = factory_business(identifier='BC1234567', entity_type='BC', founding_date=OLD_FOUNDING_DATE)
     filing = copy.deepcopy(FILING_HEADER)
     filing['filing']['agmLocationChange'] = copy.deepcopy(AGM_LOCATION_CHANGE)
     filing['filing']['header']['name'] = 'agmLocationChange'
 
+    current_year = LegislationDatetime.now().year
+    expected_min = current_year - 2
+    expected_max = current_year + 1
+
     if test_name == 'INVALID_YEAR':
         filing['filing']['agmLocationChange']['year'] = 'invalid'
     elif test_name == 'FAIL_YEAR-3':
-        filing['filing']['agmLocationChange']['year'] = str(LegislationDatetime.now().year - 3)
+        filing['filing']['agmLocationChange']['year'] = str(current_year - 3)
     elif test_name == 'FAIL_YEAR+2':
-        filing['filing']['agmLocationChange']['year'] = str(LegislationDatetime.now().year + 2)
+        filing['filing']['agmLocationChange']['year'] = str(current_year + 2)
     elif test_name == 'SUCCESS-2':
-        filing['filing']['agmLocationChange']['year'] = str(LegislationDatetime.now().year - 2)
+        filing['filing']['agmLocationChange']['year'] = str(current_year - 2)
     elif test_name == 'SUCCESS+1':
-        filing['filing']['agmLocationChange']['year'] = str(LegislationDatetime.now().year + 1)
+        filing['filing']['agmLocationChange']['year'] = str(current_year + 1)
     elif test_name == 'SUCCESS':
-        filing['filing']['agmLocationChange']['year'] = str(LegislationDatetime.now().year)
+        filing['filing']['agmLocationChange']['year'] = str(current_year)
     err = validate(business, filing)
 
     # validate outcomes
@@ -71,11 +78,54 @@ def test_validate_agm_year(session, mocker, test_name, expected_code, message, m
         assert err.code == HTTPStatus.UNPROCESSABLE_ENTITY
     elif not test_name.startswith('SUCCESS'):
         assert expected_code == err.code
-        if message:
-            assert message == err.msg[0]['error']
+        assert f'AGM year must be between {expected_min} and {expected_max}.' == err.msg[0]['error']
+    else:
+        assert not err
+
+
+@pytest.mark.parametrize(
+    'test_name, founding_years_ago, year_offset_from_now',
+    [
+        # business founded less than 2 years ago: founding year should raise the floor
+        # above the default lookback year
+        ('FAIL_BEFORE_FOUNDING_YEAR', 1, -2),
+        ('SUCCESS_AT_FOUNDING_YEAR', 1, -1),
+        # business founded this year: floor should equal the current year
+        ('FAIL_BEFORE_FOUNDING_THIS_YEAR', 0, -1),
+        ('SUCCESS_FOUNDING_THIS_YEAR', 0, 0),
+    ]
+)
+def test_validate_agm_year_founding_date_floor(
+    session, mocker, test_name, founding_years_ago, year_offset_from_now, monkeypatch
+):
+    """Assert AGM year cannot be set to a year before the business's founding year."""
+    monkeypatch.setattr(
+        'legal_api.services.flags.value',
+        lambda flag, default=None: "BC BEN CC ULC C CBEN CCC CUL" if flag == 'supported-agm-location-change-entities' else default
+    )
+    current_year = LegislationDatetime.now().year
+    founding_date = datetime.utcnow().replace(year=current_year - founding_years_ago)
+    business = factory_business(identifier='BC1234567', entity_type='BC', founding_date=founding_date)
+
+    filing = copy.deepcopy(FILING_HEADER)
+    filing['filing']['agmLocationChange'] = copy.deepcopy(AGM_LOCATION_CHANGE)
+    filing['filing']['header']['name'] = 'agmLocationChange'
+    filing['filing']['agmLocationChange']['year'] = str(current_year + year_offset_from_now)
+
+    err = validate(business, filing)
+
+    founding_year = current_year - founding_years_ago
+    expected_min = max(current_year - 2, founding_year)
+    expected_max = current_year + 1
+
+    if test_name.startswith('FAIL'):
+        assert err is not None
+        assert err.code == HTTPStatus.BAD_REQUEST
+        assert f'AGM year must be between {expected_min} and {expected_max}.' == err.msg[0]['error']
     else:
         assert not err
 
+
 @pytest.mark.parametrize(
     'test_name, reason, expected_code, message',
     [
@@ -91,7 +141,7 @@ def test_validate_agm_reason(session, mocker, test_name, reason, expected_code,
         'legal_api.services.flags.value',
         lambda flag, default=None: "BC BEN CC ULC C CBEN CCC CUL" if flag == 'supported-agm-location-change-entities' else default
     )
-    business = factory_business(identifier='BC1234567', entity_type='BC', founding_date=datetime.utcnow())
+    business = factory_business(identifier='BC1234567', entity_type='BC', founding_date=OLD_FOUNDING_DATE)
     filing = copy.deepcopy(FILING_HEADER)
     filing['filing']['agmLocationChange'] = copy.deepcopy(AGM_LOCATION_CHANGE)
     filing['filing']['header']['name'] = 'agmLocationChange'