diff --git a/dandischema/models.py b/dandischema/models.py
index c91afad0..791e8142 100644
--- a/dandischema/models.py
+++ b/dandischema/models.py
@@ -11,7 +11,6 @@
     List,
     Literal,
     Optional,
-    Sequence,
     Type,
     TypeVar,
     Union,
@@ -928,7 +927,7 @@ class Contributor(DandiBaseModel):
         description="Identifier associated with a sponsored or gift award.",
         json_schema_extra={"nskey": DANDI_NSKEY},
     )
-    schemaKey: Literal["Contributor", "Organization", "Person"] = Field(
+    schemaKey: Literal["Contributor"] = Field(
         "Contributor", validate_default=True, json_schema_extra={"readOnly": True}
     )
 
@@ -965,7 +964,7 @@ class Organization(Contributor):
         description="Contact for the organization",
         json_schema_extra={"nskey": "schema"},
     )
-    schemaKey: Literal["Organization"] = Field(
+    schemaKey: Literal["Organization"] = Field(  # type: ignore[assignment]
         "Organization", validate_default=True, json_schema_extra={"readOnly": True}
     )
     _ldmeta = {
@@ -1014,7 +1013,7 @@ class Person(Contributor):
         description="An organization that this person is affiliated with.",
         json_schema_extra={"nskey": "schema"},
     )
-    schemaKey: Literal["Person"] = Field(
+    schemaKey: Literal["Person"] = Field(  # type: ignore[assignment]
         "Person", validate_default=True, json_schema_extra={"readOnly": True}
     )
 
@@ -1289,7 +1288,7 @@ class Activity(DandiBaseModel):
         description="A listing of equipment used for the activity.",
         json_schema_extra={"nskey": "prov"},
     )
-    schemaKey: Literal["Activity", "Project", "Session", "PublishActivity"] = Field(
+    schemaKey: Literal["Activity"] = Field(
         "Activity", validate_default=True, json_schema_extra={"readOnly": True}
     )
 
@@ -1311,7 +1310,7 @@ class Project(Activity):
         description="A brief description of the project.",
         json_schema_extra={"nskey": "schema"},
     )
-    schemaKey: Literal["Project"] = Field(
+    schemaKey: Literal["Project"] = Field(  # type: ignore[assignment]
         "Project", validate_default=True, json_schema_extra={"readOnly": True}
     )
 
@@ -1328,13 +1327,13 @@ class Session(Activity):
         description="A brief description of the session.",
         json_schema_extra={"nskey": "schema"},
     )
-    schemaKey: Literal["Session"] = Field(
+    schemaKey: Literal["Session"] = Field(  # type: ignore[assignment]
         "Session", validate_default=True, json_schema_extra={"readOnly": True}
     )
 
 
 class PublishActivity(Activity):
-    schemaKey: Literal["PublishActivity"] = Field(
+    schemaKey: Literal["PublishActivity"] = Field(  # type: ignore[assignment]
         "PublishActivity", validate_default=True, json_schema_extra={"readOnly": True}
     )
 
@@ -1637,9 +1636,9 @@ class CommonModel(DandiBaseModel):
         None, json_schema_extra={"nskey": DANDI_NSKEY}
     )
 
-    wasGeneratedBy: Optional[Sequence[Activity]] = Field(
-        None, json_schema_extra={"nskey": "prov"}
-    )
+    wasGeneratedBy: Optional[
+        list[Union[Activity, Project, PublishActivity, Session]]
+    ] = Field(None, json_schema_extra={"nskey": "prov"})
     schemaKey: str = Field(
         "CommonModel", validate_default=True, json_schema_extra={"readOnly": True}
     )
@@ -1784,7 +1783,7 @@ def contributor_musthave_contact(
         json_schema_extra={"readOnly": True, "nskey": "schema"},
     )
 
-    wasGeneratedBy: Optional[Sequence[Project]] = Field(
+    wasGeneratedBy: Optional[list[Project]] = Field(  # type: ignore[assignment]
         None,
         title="Associated projects",
         description="Project(s) that generated this Dandiset.",
@@ -1927,10 +1926,12 @@ class BareAsset(CommonModel):
         description="Associated participant(s) or subject(s).",
         json_schema_extra={"nskey": "prov"},
     )
-    wasGeneratedBy: Optional[List[Union[Session, Project, Activity]]] = Field(
+    wasGeneratedBy: Optional[
+        list[Union[Activity, Project, PublishActivity, Session]]
+    ] = Field(
         None,
-        title="Name of the session, project or activity.",
-        description="Describe the session, project or activity that generated this asset.",
+        title="Associated activities",
+        description="Activities that generated this asset.",
         json_schema_extra={"nskey": "prov"},
     )