diff --git a/PyPDFForm/constants.py b/PyPDFForm/constants.py
index 1adfc6f2..1b39dd25 100644
--- a/PyPDFForm/constants.py
+++ b/PyPDFForm/constants.py
@@ -48,7 +48,6 @@
 MK = "/MK"
 CA = "/CA"
 AS = "/AS"
-Yes = "/Yes"
 Off = "/Off"
 
 # Field flag bits
diff --git a/PyPDFForm/patterns.py b/PyPDFForm/patterns.py
index 6e3e53c0..b2681bbe 100644
--- a/PyPDFForm/patterns.py
+++ b/PyPDFForm/patterns.py
@@ -5,7 +5,7 @@
                            TextStringObject)
 
 from .constants import (AP, AS, CA, DA, FT, MK, READ_ONLY, Btn, Ch, D, Ff, Off,
-                        Opt, Parent, Q, Sig, Subtype, T, Tx, V, Widget, Yes)
+                        Opt, Parent, Q, Sig, Subtype, T, Tx, V, Widget)
 from .middleware.checkbox import Checkbox
 from .middleware.dropdown import Dropdown
 from .middleware.radio import Radio
@@ -83,7 +83,10 @@
 def simple_update_checkbox_value(annot: DictionaryObject) -> None:
     """Patterns to update values for checkbox annotations."""
 
-    annot[NameObject(AS)] = NameObject(Yes)
+    for each in annot[AP][D]:  # noqa
+        if str(each) != Off:
+            annot[NameObject(AS)] = NameObject(each)
+            break
 
 
 def simple_update_radio_value(annot: DictionaryObject) -> None:
diff --git a/pdf_samples/simple/scenario/existed/illinois-gun-bill-of-sale_expected.pdf b/pdf_samples/simple/scenario/existed/illinois-gun-bill-of-sale_expected.pdf
new file mode 100644
index 00000000..e96bc1c2
Binary files /dev/null and b/pdf_samples/simple/scenario/existed/illinois-gun-bill-of-sale_expected.pdf differ
diff --git a/tests/scenario/test_existed_simple.py b/tests/scenario/test_existed_simple.py
index fedd5507..79d9df54 100644
--- a/tests/scenario/test_existed_simple.py
+++ b/tests/scenario/test_existed_simple.py
@@ -5,6 +5,54 @@
 from PyPDFForm import FormWrapper
 
 
+def test_illinois_gun_bill_of_sale(existed_pdf_directory, pdf_samples, request):
+    expected_path = os.path.join(
+        pdf_samples, "simple", "scenario", "existed", "illinois-gun-bill-of-sale_expected.pdf"
+    )
+    with open(expected_path, "rb+") as f:
+        obj = FormWrapper(os.path.join(existed_pdf_directory, "illinois-gun-bill-of-sale.pdf")).fill(
+            {
+                "Date": "01-01",
+                "20": "22",
+                "Buyers Name": "John Doe",
+                "undefined": "1 N Main St, Chicago, IL 60000",
+                "Sellers Name": "Jack Smith",
+                "undefined_2": "2 S Main St, Chicago, IL 60000",
+                "Make": "AK",
+                "TypeModel": "47",
+                "Caliber": "7.62-x39mm",
+                "Serial Number SN": "111111",
+                "Seller accepts cash payment in the amount of": True,
+                "The date of this bill of sale": True,
+                "At a future date no later than": True,
+                "Other": True,
+                "undefined_4": "NO REASONS",
+                "to": "400",
+                "undefined_3": "01-01",
+                "20_2": "23",
+                "undefined_5": "Food",
+                "Buyer is receiving the Firearm as a Gift": True,
+                "Seller accepts trade for the Firearm in exchange for": True,
+                "Print Name": "John Doe",
+                "Print Name_2": "Jack Smith",
+                "Date_2": "2021-01-01",
+                "Date_3": "2021-01-01",
+                "Drivers License Number": "D000-4609-0001",
+                "Drivers License Number_2": "S530-4209-0001",
+                "State": "IL",
+                "State_2": "IL",
+            }
+        )
+
+        request.config.results["expected_path"] = expected_path
+        request.config.results["stream"] = obj.read()
+
+        expected = f.read()
+
+        assert len(obj.read()) == len(expected)
+        assert obj.stream == expected
+
+
 def test_ds82(existed_pdf_directory, pdf_samples, request):
     expected_path = os.path.join(
         pdf_samples, "simple", "scenario", "existed", "DS82_expected.pdf"