diff --git a/src/codemodder/codetf/common.py b/src/codemodder/codetf/common.py
index 011809c0..fa1086ec 100644
--- a/src/codemodder/codetf/common.py
+++ b/src/codemodder/codetf/common.py
@@ -1,8 +1,9 @@
 from abc import ABCMeta
 from enum import Enum
 from pathlib import Path
+from typing import Optional
 
-from pydantic import BaseModel
+from pydantic import BaseModel, ConfigDict, model_validator
 
 from codemodder.logging import logger
 
@@ -26,3 +27,60 @@ def write_report(self, outfile: Path | str) -> int:
             return 2
         logger.debug("wrote report to %s", outfile)
         return 0
+
+
+class Rule(BaseModel):
+    id: str
+    name: str
+    url: Optional[str] = None
+
+    model_config = ConfigDict(frozen=True)
+
+
+class Finding(BaseModel):
+    id: str
+    rule: Rule
+
+    model_config = ConfigDict(frozen=True)
+
+
+class Action(CaseInsensitiveEnum):
+    ADD = "add"
+    REMOVE = "remove"
+
+
+class PackageResult(CaseInsensitiveEnum):
+    COMPLETED = "completed"
+    FAILED = "failed"
+    SKIPPED = "skipped"
+
+
+class DiffSide(CaseInsensitiveEnum):
+    LEFT = "left"
+    RIGHT = "right"
+
+
+class PackageAction(BaseModel):
+    action: Action
+    result: PackageResult
+    package: str
+
+
+class Change(BaseModel):
+    lineNumber: int
+    description: Optional[str]
+    diffSide: DiffSide = DiffSide.RIGHT
+    properties: Optional[dict] = None
+    packageActions: Optional[list[PackageAction]] = None
+
+    @model_validator(mode="after")
+    def validate_lineNumber(self):
+        if self.lineNumber < 1:
+            raise ValueError("lineNumber must be greater than 0")
+        return self
+
+    @model_validator(mode="after")
+    def validate_description(self):
+        if self.description is not None and not self.description:
+            raise ValueError("description must not be empty")
+        return self
diff --git a/src/codemodder/codetf/v2/codetf.py b/src/codemodder/codetf/v2/codetf.py
index fefb9f5d..863fe527 100644
--- a/src/codemodder/codetf/v2/codetf.py
+++ b/src/codemodder/codetf/v2/codetf.py
@@ -11,11 +11,21 @@
 from enum import Enum
 from typing import TYPE_CHECKING, Optional
 
-from pydantic import BaseModel, ConfigDict, model_validator
+from pydantic import BaseModel, model_validator
 
 from codemodder import __version__
 
-from ..common import CaseInsensitiveEnum, CodeTFWriter
+from ..common import (
+    CaseInsensitiveEnum,
+)
+from ..common import Change as CommonChange
+from ..common import (
+    CodeTFWriter,
+)
+from ..common import Finding as CommonFinding
+from ..common import (
+    Rule,
+)
 
 if TYPE_CHECKING:
     from codemodder.context import CodemodExecutionContext
@@ -46,10 +56,6 @@ class PackageAction(BaseModel):
 class Change(BaseModel):
     lineNumber: int
     description: Optional[str]
-    # All of our changes are currently treated as additive, so it makes sense
-    # for the comments to appear on the RIGHT side of the split diff. Eventually we
-    # may want to differentiate between LEFT and RIGHT, but for now we'll just
-    # default to RIGHT.
     diffSide: DiffSide = DiffSide.RIGHT
     properties: Optional[dict] = None
     packageActions: Optional[list[PackageAction]] = None
@@ -77,6 +83,15 @@ def with_findings(self, findings: list[Finding] | None) -> Change:
             fixedFindings=findings,
         )
 
+    def to_common(self) -> CommonChange:
+        return CommonChange(
+            lineNumber=self.lineNumber,
+            description=self.description,
+            diffSide=self.diffSide,
+            properties=self.properties,
+            packageActions=self.packageActions,
+        )
+
 
 class AIMetadata(BaseModel):
     provider: Optional[str] = None
@@ -138,20 +153,7 @@ def validate_description(self):
         return self
 
 
-class Rule(BaseModel):
-    id: str
-    name: str
-    url: Optional[str] = None
-
-    model_config = ConfigDict(frozen=True)
-
-
-class Finding(BaseModel):
-    id: Optional[str] = None
-    rule: Rule
-
-    model_config = ConfigDict(frozen=True)
-
+class Finding(CommonFinding):
     def to_unfixed_finding(
         self,
         *,
@@ -170,7 +172,7 @@ def to_unfixed_finding(
     def with_rule(self, name: str, url: Optional[str]) -> Finding:
         return Finding(
             id=self.id,
-            rule=Rule(id=self.rule.id, name=name, url=url),
+            rule=Rule(id=self.rule.id, name=name, url=url) if self.rule else None,
         )
 
 
diff --git a/src/codemodder/codetf/v3/codetf.py b/src/codemodder/codetf/v3/codetf.py
index 1ed7e50d..255b8cec 100644
--- a/src/codemodder/codetf/v3/codetf.py
+++ b/src/codemodder/codetf/v3/codetf.py
@@ -5,7 +5,8 @@
 
 from pydantic import BaseModel, model_validator
 
-from ..common import CaseInsensitiveEnum, CodeTFWriter
+from ..common import Change, CodeTFWriter, Finding
+from ..v2.codetf import Finding as V2Finding
 
 
 class Run(BaseModel):
@@ -44,59 +45,6 @@ class FixStatus(BaseModel):
     details: Optional[str]
 
 
-class Rule(BaseModel):
-    id: str
-    name: str
-    url: Optional[str] = None
-
-
-class Finding(BaseModel):
-    id: str
-    rule: Optional[Rule] = None
-
-
-class Action(CaseInsensitiveEnum):
-    ADD = "add"
-    REMOVE = "remove"
-
-
-class PackageResult(CaseInsensitiveEnum):
-    COMPLETED = "completed"
-    FAILED = "failed"
-    SKIPPED = "skipped"
-
-
-class DiffSide(CaseInsensitiveEnum):
-    LEFT = "left"
-    RIGHT = "right"
-
-
-class PackageAction(BaseModel):
-    action: Action
-    result: PackageResult
-    package: str
-
-
-class Change(BaseModel):
-    lineNumber: int
-    description: Optional[str]
-    diffSide: DiffSide = DiffSide.RIGHT
-    properties: Optional[dict] = None
-    packageActions: Optional[list[PackageAction]] = None
-
-    @model_validator(mode="after")
-    def validate_lineNumber(self):
-        if self.lineNumber < 1:
-            raise ValueError("lineNumber must be greater than 0")
-        return self
-
-    @model_validator(mode="after")
-    def validate_description(self):
-        if self.description is not None and not self.description:
-            raise ValueError("description must not be empty")
-        return self
-
-
 class ChangeSet(BaseModel):
     path: str
     diff: str
@@ -158,7 +106,7 @@ class FixQuality(BaseModel):
 class FixResult(BaseModel):
     """Result corresponding to a single finding"""
 
-    finding: Finding
+    finding: Finding | V2Finding
     fixStatus: FixStatus
     changeSets: list[ChangeSet]
     fixMetadata: Optional[FixMetadata] = None