diff --git a/Tests/mtiLib/data/mti/gposkernset.ttx.GPOS b/Tests/mtiLib/data/mti/gposkernset.ttx.GPOS
index 30e66d49d..a8371233b 100644
--- a/Tests/mtiLib/data/mti/gposkernset.ttx.GPOS
+++ b/Tests/mtiLib/data/mti/gposkernset.ttx.GPOS
@@ -44,7 +44,7 @@
         </Coverage>
         <ValueFormat1 value="4"/>
         <ValueFormat2 value="0"/>
-        <ClassDef1 Format="2">
+        <ClassDef1>
           <ClassDef glyph="A" class="1"/>
           <ClassDef glyph="Aacute" class="1"/>
           <ClassDef glyph="Acircumflex" class="1"/>
@@ -55,7 +55,7 @@
           <ClassDef glyph="Ograve" class="2"/>
           <ClassDef glyph="T" class="3"/>
         </ClassDef1>
-        <ClassDef2 Format="2">
+        <ClassDef2>
           <ClassDef glyph="V" class="1"/>
           <ClassDef glyph="a" class="2"/>
           <ClassDef glyph="aacute" class="2"/>
diff --git a/Tests/mtiLib/data/mti/gpospairclass.ttx.GPOS b/Tests/mtiLib/data/mti/gpospairclass.ttx.GPOS
index 319cd170d..32b35aee9 100644
--- a/Tests/mtiLib/data/mti/gpospairclass.ttx.GPOS
+++ b/Tests/mtiLib/data/mti/gpospairclass.ttx.GPOS
@@ -21,7 +21,7 @@
         </Coverage>
         <ValueFormat1 value="4"/>
         <ValueFormat2 value="0"/>
-        <ClassDef1 Format="2">
+        <ClassDef1>
           <ClassDef glyph="A" class="1"/>
           <ClassDef glyph="Aacute" class="1"/>
           <ClassDef glyph="Acircumflex" class="1"/>
@@ -32,7 +32,7 @@
           <ClassDef glyph="Ograve" class="2"/>
           <ClassDef glyph="T" class="3"/>
         </ClassDef1>
-        <ClassDef2 Format="2">
+        <ClassDef2>
           <ClassDef glyph="V" class="1"/>
           <ClassDef glyph="a" class="2"/>
           <ClassDef glyph="aacute" class="2"/>
diff --git a/Tests/subset/data/test_cntrmask_CFF.ttx b/Tests/subset/data/test_cntrmask_CFF.ttx
index d52b0e5b2..9e7d20514 100644
--- a/Tests/subset/data/test_cntrmask_CFF.ttx
+++ b/Tests/subset/data/test_cntrmask_CFF.ttx
@@ -340,10 +340,10 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="1">
+          <ClassDef1>
             <ClassDef glyph="Idieresis" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="2">
+          <ClassDef2>
           </ClassDef2>
           <!-- Class1Count=2 -->
           <!-- Class2Count=1 -->
diff --git a/Tests/ttLib/tables/data/aots/gpos2_2_font1.ttx.GPOS b/Tests/ttLib/tables/data/aots/gpos2_2_font1.ttx.GPOS
index 144f9c224..d41d02ddc 100644
--- a/Tests/ttLib/tables/data/aots/gpos2_2_font1.ttx.GPOS
+++ b/Tests/ttLib/tables/data/aots/gpos2_2_font1.ttx.GPOS
@@ -39,10 +39,10 @@
           </Coverage>
           <ValueFormat1 value="1"/>
           <ValueFormat2 value="2"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
             <ClassDef glyph="g18" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="2">
+          <ClassDef2>
             <ClassDef glyph="g19" class="1"/>
           </ClassDef2>
           <!-- Class1Count=2 -->
diff --git a/Tests/ttLib/tables/data/aots/gpos2_2_font2.ttx.GPOS b/Tests/ttLib/tables/data/aots/gpos2_2_font2.ttx.GPOS
index afb6d0917..c7f3f3289 100644
--- a/Tests/ttLib/tables/data/aots/gpos2_2_font2.ttx.GPOS
+++ b/Tests/ttLib/tables/data/aots/gpos2_2_font2.ttx.GPOS
@@ -39,10 +39,10 @@
           </Coverage>
           <ValueFormat1 value="1"/>
           <ValueFormat2 value="2"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
             <ClassDef glyph="g19" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="2">
+          <ClassDef2>
             <ClassDef glyph="g20" class="1"/>
           </ClassDef2>
           <!-- Class1Count=2 -->
diff --git a/Tests/ttLib/tables/data/aots/gpos2_2_font3.ttx.GPOS b/Tests/ttLib/tables/data/aots/gpos2_2_font3.ttx.GPOS
index 264a20415..25ac07ca2 100644
--- a/Tests/ttLib/tables/data/aots/gpos2_2_font3.ttx.GPOS
+++ b/Tests/ttLib/tables/data/aots/gpos2_2_font3.ttx.GPOS
@@ -39,10 +39,10 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="2"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
             <ClassDef glyph="g19" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="2">
+          <ClassDef2>
             <ClassDef glyph="g20" class="1"/>
           </ClassDef2>
           <!-- Class1Count=2 -->
diff --git a/Tests/ttLib/tables/data/aots/gpos2_2_font4.ttx.GPOS b/Tests/ttLib/tables/data/aots/gpos2_2_font4.ttx.GPOS
index 672792d06..46f3e6eee 100644
--- a/Tests/ttLib/tables/data/aots/gpos2_2_font4.ttx.GPOS
+++ b/Tests/ttLib/tables/data/aots/gpos2_2_font4.ttx.GPOS
@@ -39,10 +39,10 @@
           </Coverage>
           <ValueFormat1 value="1"/>
           <ValueFormat2 value="2"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
             <ClassDef glyph="g18" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="2">
+          <ClassDef2>
             <ClassDef glyph="g18" class="1"/>
           </ClassDef2>
           <!-- Class1Count=2 -->
diff --git a/Tests/ttLib/tables/data/aots/gpos2_2_font5.ttx.GPOS b/Tests/ttLib/tables/data/aots/gpos2_2_font5.ttx.GPOS
index 62364cfdb..1d589ca2e 100644
--- a/Tests/ttLib/tables/data/aots/gpos2_2_font5.ttx.GPOS
+++ b/Tests/ttLib/tables/data/aots/gpos2_2_font5.ttx.GPOS
@@ -39,10 +39,10 @@
           </Coverage>
           <ValueFormat1 value="1"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
             <ClassDef glyph="g18" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="2">
+          <ClassDef2>
             <ClassDef glyph="g18" class="1"/>
           </ClassDef2>
           <!-- Class1Count=2 -->
diff --git a/Tests/varLib/data/master_kerning_merging/0.ttx b/Tests/varLib/data/master_kerning_merging/0.ttx
index c27e4521c..1ca22f68e 100644
--- a/Tests/varLib/data/master_kerning_merging/0.ttx
+++ b/Tests/varLib/data/master_kerning_merging/0.ttx
@@ -272,10 +272,10 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="1">
+          <ClassDef1>
             <ClassDef glyph="A" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="C" class="1"/>
           </ClassDef2>
           <!-- Class1Count=2 -->
diff --git a/Tests/varLib/data/master_kerning_merging/1.ttx b/Tests/varLib/data/master_kerning_merging/1.ttx
index 6cd212dbe..9f6756d8e 100644
--- a/Tests/varLib/data/master_kerning_merging/1.ttx
+++ b/Tests/varLib/data/master_kerning_merging/1.ttx
@@ -265,9 +265,9 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="B" class="2"/>
             <ClassDef glyph="D" class="1"/>
           </ClassDef2>
diff --git a/Tests/varLib/data/master_kerning_merging/2.ttx b/Tests/varLib/data/master_kerning_merging/2.ttx
index 93b250d65..b8302e8b1 100644
--- a/Tests/varLib/data/master_kerning_merging/2.ttx
+++ b/Tests/varLib/data/master_kerning_merging/2.ttx
@@ -272,10 +272,10 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="1">
+          <ClassDef1>
             <ClassDef glyph="A" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="D" class="1"/>
           </ClassDef2>
           <!-- Class1Count=2 -->
diff --git a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Bold.ttx b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Bold.ttx
index 08261c3f8..0f9e97a51 100644
--- a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Bold.ttx
+++ b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Bold.ttx
@@ -485,9 +485,9 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="T" class="4"/>
             <ClassDef glyph="n" class="3"/>
             <ClassDef glyph="o" class="2"/>
diff --git a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Condensed.ttx b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Condensed.ttx
index 622d1e28c..f8ff98786 100644
--- a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Condensed.ttx
+++ b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Condensed.ttx
@@ -491,9 +491,9 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="T" class="4"/>
             <ClassDef glyph="n" class="3"/>
             <ClassDef glyph="o" class="2"/>
diff --git a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-CondensedBold.ttx b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-CondensedBold.ttx
index b2b3a1a1c..2b7264d18 100644
--- a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-CondensedBold.ttx
+++ b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-CondensedBold.ttx
@@ -491,9 +491,9 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="T" class="4"/>
             <ClassDef glyph="n" class="3"/>
             <ClassDef glyph="o" class="2"/>
diff --git a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-CondensedLight.ttx b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-CondensedLight.ttx
index d7b769223..d03abf5fa 100644
--- a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-CondensedLight.ttx
+++ b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-CondensedLight.ttx
@@ -491,9 +491,9 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="T" class="4"/>
             <ClassDef glyph="n" class="3"/>
             <ClassDef glyph="o" class="2"/>
diff --git a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-CondensedSemiBold.ttx b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-CondensedSemiBold.ttx
index c4701edef..118922099 100644
--- a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-CondensedSemiBold.ttx
+++ b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-CondensedSemiBold.ttx
@@ -491,9 +491,9 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="T" class="4"/>
             <ClassDef glyph="n" class="3"/>
             <ClassDef glyph="o" class="2"/>
diff --git a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Light.ttx b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Light.ttx
index 486b3382d..3583c0d3e 100644
--- a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Light.ttx
+++ b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Light.ttx
@@ -491,9 +491,9 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="T" class="4"/>
             <ClassDef glyph="n" class="3"/>
             <ClassDef glyph="o" class="2"/>
diff --git a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Regular.ttx b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Regular.ttx
index 70c0dc731..bf68b1673 100644
--- a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Regular.ttx
+++ b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-Regular.ttx
@@ -485,9 +485,9 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="T" class="4"/>
             <ClassDef glyph="n" class="3"/>
             <ClassDef glyph="o" class="2"/>
diff --git a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-SemiBold.ttx b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-SemiBold.ttx
index b462f8f99..96badb343 100644
--- a/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-SemiBold.ttx
+++ b/Tests/varLib/data/master_ttx_interpolatable_ttf/TestFamily3-SemiBold.ttx
@@ -491,9 +491,9 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="T" class="4"/>
             <ClassDef glyph="n" class="3"/>
             <ClassDef glyph="o" class="2"/>
diff --git a/Tests/varLib/data/test_results/InterpolateLayoutGPOS_2_class_diff.ttx b/Tests/varLib/data/test_results/InterpolateLayoutGPOS_2_class_diff.ttx
index 9c2438bb2..0aeb49737 100644
--- a/Tests/varLib/data/test_results/InterpolateLayoutGPOS_2_class_diff.ttx
+++ b/Tests/varLib/data/test_results/InterpolateLayoutGPOS_2_class_diff.ttx
@@ -39,9 +39,9 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="a" class="1"/>
           </ClassDef2>
           <!-- Class1Count=1 -->
diff --git a/Tests/varLib/data/test_results/InterpolateLayoutGPOS_2_class_diff2.ttx b/Tests/varLib/data/test_results/InterpolateLayoutGPOS_2_class_diff2.ttx
index 7609e293b..f00c4c3a3 100644
--- a/Tests/varLib/data/test_results/InterpolateLayoutGPOS_2_class_diff2.ttx
+++ b/Tests/varLib/data/test_results/InterpolateLayoutGPOS_2_class_diff2.ttx
@@ -40,10 +40,10 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="1">
+          <ClassDef1>
             <ClassDef glyph="a" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="a" class="1"/>
           </ClassDef2>
           <!-- Class1Count=2 -->
diff --git a/Tests/varLib/data/test_results/InterpolateLayoutGPOS_2_class_same.ttx b/Tests/varLib/data/test_results/InterpolateLayoutGPOS_2_class_same.ttx
index 6127d1aec..3656964b7 100644
--- a/Tests/varLib/data/test_results/InterpolateLayoutGPOS_2_class_same.ttx
+++ b/Tests/varLib/data/test_results/InterpolateLayoutGPOS_2_class_same.ttx
@@ -39,9 +39,9 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="2">
+          <ClassDef1>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="a" class="1"/>
           </ClassDef2>
           <!-- Class1Count=1 -->
diff --git a/Tests/varLib/instancer/data/PartialInstancerTest2-VF.ttx b/Tests/varLib/instancer/data/PartialInstancerTest2-VF.ttx
index f86042a0b..cd7ffa05e 100644
--- a/Tests/varLib/instancer/data/PartialInstancerTest2-VF.ttx
+++ b/Tests/varLib/instancer/data/PartialInstancerTest2-VF.ttx
@@ -659,12 +659,12 @@
           </Coverage>
           <ValueFormat1 value="68"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="1">
+          <ClassDef1>
             <ClassDef glyph="A" class="1"/>
             <ClassDef glyph="Agrave" class="1"/>
             <ClassDef glyph="T" class="2"/>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="A" class="1"/>
             <ClassDef glyph="Agrave" class="1"/>
             <ClassDef glyph="T" class="2"/>
diff --git a/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-100,100.ttx b/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-100,100.ttx
index b078ea60d..776a92f18 100644
--- a/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-100,100.ttx
+++ b/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-100,100.ttx
@@ -427,10 +427,10 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="1">
+          <ClassDef1>
             <ClassDef glyph="T" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="A" class="1"/>
             <ClassDef glyph="Agrave" class="1"/>
             <ClassDef glyph="T" class="2"/>
diff --git a/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-100,62.5.ttx b/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-100,62.5.ttx
index b885e2d04..61bc41cc3 100644
--- a/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-100,62.5.ttx
+++ b/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-100,62.5.ttx
@@ -427,10 +427,10 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="1">
+          <ClassDef1>
             <ClassDef glyph="T" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="A" class="1"/>
             <ClassDef glyph="Agrave" class="1"/>
             <ClassDef glyph="T" class="2"/>
diff --git a/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-400,100.ttx b/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-400,100.ttx
index f709ca6ae..c2d205715 100644
--- a/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-400,100.ttx
+++ b/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-400,100.ttx
@@ -421,10 +421,10 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="1">
+          <ClassDef1>
             <ClassDef glyph="T" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="A" class="1"/>
             <ClassDef glyph="Agrave" class="1"/>
             <ClassDef glyph="T" class="2"/>
diff --git a/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-400,62.5.ttx b/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-400,62.5.ttx
index f768db133..63eeb0e7f 100644
--- a/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-400,62.5.ttx
+++ b/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-400,62.5.ttx
@@ -427,10 +427,10 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="1">
+          <ClassDef1>
             <ClassDef glyph="T" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="A" class="1"/>
             <ClassDef glyph="Agrave" class="1"/>
             <ClassDef glyph="T" class="2"/>
diff --git a/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-900,100.ttx b/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-900,100.ttx
index dc8ad600b..013ba1e73 100644
--- a/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-900,100.ttx
+++ b/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-900,100.ttx
@@ -427,10 +427,10 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="1">
+          <ClassDef1>
             <ClassDef glyph="T" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="A" class="1"/>
             <ClassDef glyph="Agrave" class="1"/>
             <ClassDef glyph="T" class="2"/>
diff --git a/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-900,62.5.ttx b/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-900,62.5.ttx
index decabc3c8..45e34cbf7 100644
--- a/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-900,62.5.ttx
+++ b/Tests/varLib/instancer/data/test_results/PartialInstancerTest2-VF-instance-900,62.5.ttx
@@ -427,10 +427,10 @@
           </Coverage>
           <ValueFormat1 value="4"/>
           <ValueFormat2 value="0"/>
-          <ClassDef1 Format="1">
+          <ClassDef1>
             <ClassDef glyph="T" class="1"/>
           </ClassDef1>
-          <ClassDef2 Format="1">
+          <ClassDef2>
             <ClassDef glyph="A" class="1"/>
             <ClassDef glyph="Agrave" class="1"/>
             <ClassDef glyph="T" class="2"/>