diff --git a/Rules/Braille/Russian/Russian_Rules.yaml b/Rules/Braille/Russian/Russian_Rules.yaml
index 4ab7154a..a691101e 100644
--- a/Rules/Braille/Russian/Russian_Rules.yaml
+++ b/Rules/Braille/Russian/Russian_Rules.yaml
@@ -93,6 +93,17 @@
   - x: "*[1]"
   - t: "⠹"
 
+-
+  name: nested-fraction
+  tag: mfrac
+  match: "parent::m:mfrac"
+  replace:
+  - t: "⠆"
+  - x: "*[1]"
+  - t: "⠀⠳"
+  - x: "*[2]"
+  - t: "⠰"
+
 -
   name: simple-numeric
   tag: mfrac
@@ -267,6 +278,41 @@
   - t: "#"
   - x: "*[1]"
 
+-
+  name: signed-integer-number
+  tag: [msub, munder]
+  match: "*[2][self::m:mn and (substring(., 1, 1)='-' or substring(., 1, 1)='−' or substring(., 1, 1)='+') and translate(substring(., 2), '0123456789', '')='']"
+  replace:
+  - x: "*[1]"
+  - test:
+      if: "self::m:munder"
+      then: [t: "⠨⠡"]
+      else: [t: "⠡"]
+  - test:
+      if: "substring(*[2], 1, 1)='+'"
+      then: [t: "⠖"]
+      else: [t: "⠤"]
+  - x: "BrailleChars(translate(substring(*[2], 2), '0123456789', '\ue000\ue001\ue002\ue003\ue004\ue005\ue006\ue007\ue008\ue009'), 'Russian')"
+
+-
+  name: signed-integer
+  tag: [msub, munder]
+  match:
+  - "*[2][self::m:mrow and count(*)=2 and"
+  - " *[1][self::m:mo][.='-' or .='−' or .='+'] and"
+  - " *[2][self::m:mn and translate(., '0123456789', '')='']]"
+  replace:
+  - x: "*[1]"
+  - test:
+      if: "self::m:munder"
+      then: [t: "⠨⠡"]
+      else: [t: "⠡"]
+  - test:
+      if: "*[2]/*[1][.='+']"
+      then: [t: "⠖"]
+      else: [t: "⠤"]
+  - x: "BrailleChars(translate(*[2]/*[2], '0123456789', '\ue000\ue001\ue002\ue003\ue004\ue005\ue006\ue007\ue008\ue009'), 'Russian')"
+
 -
   name: integer
   tag: [msub, munder]
@@ -289,9 +335,47 @@
       if: "self::m:munder"
       then: [t: "⠨⠡"]
       else: [t: "⠡"]
+  - test:
+      if: "*[2][self::m:mrow[m:mo[.='+']] or self::m:mfrac]"
+      then: [t: "⠐"]
   - x: "*[2]"
   - t: "⠱"
 
+-
+  name: signed-integer-number
+  tag: [msup, mover]
+  match: "*[2][self::m:mn and (substring(., 1, 1)='-' or substring(., 1, 1)='−' or substring(., 1, 1)='+') and translate(substring(., 2), '0123456789', '')='']"
+  replace:
+  - x: "*[1]"
+  - test:
+      if: "self::m:mover"
+      then: [t: "⠨⠌"]
+      else: [t: "⠌"]
+  - test:
+      if: "substring(*[2], 1, 1)='+'"
+      then: [t: "⠖"]
+      else: [t: "⠤"]
+  - x: "BrailleChars(translate(substring(*[2], 2), '0123456789', '\ue000\ue001\ue002\ue003\ue004\ue005\ue006\ue007\ue008\ue009'), 'Russian')"
+
+-
+  name: signed-integer
+  tag: [msup, mover]
+  match:
+  - "*[2][self::m:mrow and count(*)=2 and"
+  - " *[1][self::m:mo][.='-' or .='−' or .='+'] and"
+  - " *[2][self::m:mn and translate(., '0123456789', '')='']]"
+  replace:
+  - x: "*[1]"
+  - test:
+      if: "self::m:mover"
+      then: [t: "⠨⠌"]
+      else: [t: "⠌"]
+  - test:
+      if: "*[2]/*[1][.='+']"
+      then: [t: "⠖"]
+      else: [t: "⠤"]
+  - x: "BrailleChars(translate(*[2]/*[2], '0123456789', '\ue000\ue001\ue002\ue003\ue004\ue005\ue006\ue007\ue008\ue009'), 'Russian')"
+
 -
   name: chemistry-repeated-charge
   tag: msup
@@ -457,6 +541,9 @@
       if: "self::m:munderover"
       then: [t: "⠨⠡"]
       else: [t: "⠡"]
+  - test:
+      if: "*[2][self::m:mrow[m:mo[.='+']] or self::m:mfrac]"
+      then: [t: "⠐"]
   - x: "*[2]"
   - test:
       if: "self::m:munderover"
diff --git a/tests/braille/Russian/russian.rs b/tests/braille/Russian/russian.rs
index 859d230a..4d2f9c83 100644
--- a/tests/braille/Russian/russian.rs
+++ b/tests/braille/Russian/russian.rs
@@ -1,6 +1,108 @@
 use crate::common::*;
 use anyhow::Result;
 
+#[test]
+fn script_grouping_regressions() -> Result<()> {
+    let cases = vec![
+        ("sup_x", r#"<math><msup><mi>a</mi><mi>x</mi></msup></math>"#),
+        ("sup_zero", r#"<math><msup><mi>x</mi><mn>0</mn></msup></math>"#),
+        ("sup_ten", r#"<math><msup><mi>x</mi><mn>10</mn></msup></math>"#),
+        ("sup_minus_x", r#"<math><msup><mi>a</mi><mrow><mo>-</mo><mi>x</mi></mrow></msup></math>"#),
+        ("sup_minus_2", r#"<math><msup><mi>a</mi><mrow><mo>-</mo><mn>2</mn></mrow></msup></math>"#),
+        ("sup_x_plus_1", r#"<math><msup><mi>a</mi><mrow><mi>x</mi><mo>+</mo><mn>1</mn></mrow></msup></math>"#),
+        ("sup_sub_x2", r#"<math><msup><mi>a</mi><msub><mi>x</mi><mn>2</mn></msub></msup></math>"#),
+        ("sup_nested", r#"<math><msup><mi>a</mi><msup><mi>x</mi><mn>2</mn></msup></msup></math>"#),
+        ("sup_frac", r#"<math><msup><mi>a</mi><mfrac><mn>1</mn><mn>2</mn></mfrac></msup></math>"#),
+        ("sup_sqrt", r#"<math><msup><mi>a</mi><msqrt><mi>x</mi></msqrt></msup></math>"#),
+        ("sup_follow_letter", r#"<math><mrow><msup><mi>x</mi><mn>2</mn></msup><mi>y</mi></mrow></math>"#),
+        ("sup_follow_number", r#"<math><mrow><msup><mi>x</mi><mn>2</mn></msup><mn>3</mn></mrow></math>"#),
+        ("sub_x", r#"<math><msub><mi>a</mi><mi>x</mi></msub></math>"#),
+        ("sub_zero", r#"<math><msub><mi>x</mi><mn>0</mn></msub></math>"#),
+        ("sub_ten", r#"<math><msub><mi>x</mi><mn>10</mn></msub></math>"#),
+        ("sub_minus_x", r#"<math><msub><mi>a</mi><mrow><mo>-</mo><mi>x</mi></mrow></msub></math>"#),
+        ("sub_minus_2", r#"<math><msub><mi>a</mi><mrow><mo>-</mo><mn>2</mn></mrow></msub></math>"#),
+        ("sub_x_plus_1", r#"<math><msub><mi>a</mi><mrow><mi>x</mi><mo>+</mo><mn>1</mn></mrow></msub></math>"#),
+        ("sub_nested", r#"<math><msub><mi>a</mi><msub><mi>x</mi><mn>2</mn></msub></msub></math>"#),
+        ("sub_follow_letter", r#"<math><mrow><msub><mi>x</mi><mn>2</mn></msub><mi>y</mi></mrow></math>"#),
+        ("sub_follow_number", r#"<math><mrow><msub><mi>x</mi><mn>2</mn></msub><mn>3</mn></mrow></math>"#),
+        ("subsup_numeric", r#"<math><msubsup><mi>x</mi><mn>1</mn><mn>2</mn></msubsup></math>"#),
+        ("subsup_i_n", r#"<math><msubsup><mi>x</mi><mi>i</mi><mi>n</mi></msubsup></math>"#),
+        ("subsup_grouped_sub", r#"<math><msubsup><mi>x</mi><mrow><mi>i</mi><mo>+</mo><mn>1</mn></mrow><mn>2</mn></msubsup></math>"#),
+        ("subsup_grouped_sup", r#"<math><msubsup><mi>x</mi><mn>0</mn><mrow><mi>n</mi><mo>-</mo><mn>1</mn></mrow></msubsup></math>"#),
+        ("subsup_nested_sup", r#"<math><msubsup><mi>x</mi><mn>0</mn><msup><mi>n</mi><mn>2</mn></msup></msubsup></math>"#),
+        ("negative_base_sup", r#"<math><msup><mrow><mo>-</mo><mi>x</mi></mrow><mn>2</mn></msup></math>"#),
+        ("paren_base_sup", r#"<math><msup><mrow><mo>(</mo><mi>x</mi><mo>+</mo><mn>1</mn><mo>)</mo></mrow><mn>2</mn></msup></math>"#),
+        ("frac_base_sup", r#"<math><msup><mfrac><mn>1</mn><mi>x</mi></mfrac><mn>2</mn></msup></math>"#),
+        ("root_base_sup", r#"<math><msup><msqrt><mi>x</mi></msqrt><mn>2</mn></msup></math>"#),
+        ("sup_on_function", r#"<math><mrow><msup><mi>sin</mi><mn>2</mn></msup><mi>x</mi></mrow></math>"#),
+        ("log_sub_sup", r#"<math><mrow><msubsup><mi>log</mi><mn>2</mn><mn>3</mn></msubsup><mi>x</mi></mrow></math>"#),
+        ("root_index_group", r#"<math><mroot><mi>x</mi><mrow><mi>n</mi><mo>+</mo><mn>1</mn></mrow></mroot></math>"#),
+        ("root_index_sub", r#"<math><mroot><mi>x</mi><msub><mi>n</mi><mn>2</mn></msub></mroot></math>"#),
+        ("frac_num_group", r#"<math><mfrac><mrow><mi>x</mi><mo>+</mo><mn>1</mn></mrow><mi>y</mi></mfrac></math>"#),
+        ("frac_den_group", r#"<math><mfrac><mi>x</mi><mrow><mi>y</mi><mo>+</mo><mn>1</mn></mrow></mfrac></math>"#),
+        ("nested_frac", r#"<math><mfrac><mfrac><mn>1</mn><mi>x</mi></mfrac><mfrac><mn>1</mn><mi>y</mi></mfrac></mfrac></math>"#),
+        ("sup_after_fraction", r#"<math><msup><mfrac><mrow><mi>x</mi><mo>+</mo><mn>1</mn></mrow><mrow><mi>y</mi><mo>-</mo><mn>1</mn></mrow></mfrac><mn>2</mn></msup></math>"#),
+        ("sub_after_fraction", r#"<math><msub><mfrac><mrow><mi>x</mi><mo>+</mo><mn>1</mn></mrow><mrow><mi>y</mi><mo>-</mo><mn>1</mn></mrow></mfrac><mi>i</mi></msub></math>"#),
+        ("tensor_like", r#"<math><mrow><msubsup><mi>T</mi><mi>i</mi><mi>j</mi></msubsup><msubsup><mi>x</mi><mi>j</mi><mi>k</mi></msubsup></mrow></math>"#),
+        ("pre_negative_power", r#"<math><mrow><mn>2</mn><msup><mi>x</mi><mrow><mo>-</mo><mn>1</mn></mrow></msup></mrow></math>"#),
+        ("power_of_power_follow", r#"<math><mrow><msup><msup><mi>x</mi><mn>2</mn></msup><mn>3</mn></msup><mi>y</mi></mrow></math>"#),
+        ("subscripted_power_follow", r#"<math><mrow><msup><msub><mi>x</mi><mn>2</mn></msub><mn>3</mn></msup><mi>y</mi></mrow></math>"#),
+        ("power_subscript_follow", r#"<math><mrow><msub><msup><mi>x</mi><mn>2</mn></msup><mn>3</mn></msub><mi>y</mi></mrow></math>"#),
+    ];
+
+    let expected = std::collections::HashMap::from([
+        ("sup_x", "⠠⠁⠌⠭⠱"),
+        ("sup_zero", "⠠⠭⠌⠴"),
+        ("sup_ten", "⠠⠭⠌⠂⠴"),
+        ("sup_minus_x", "⠠⠁⠌⠀⠤⠭⠱"),
+        ("sup_minus_2", "⠠⠁⠌⠤⠆"),
+        ("sup_x_plus_1", "⠠⠁⠌⠭⠀⠖⠼⠁⠱"),
+        ("sup_sub_x2", "⠠⠁⠌⠭⠡⠆⠱"),
+        ("sup_nested", "⠠⠁⠌⠭⠌⠆⠱"),
+        ("sup_frac", "⠠⠁⠌⠼⠁⠆⠱"),
+        ("sup_sqrt", "⠠⠁⠌⠩⠱⠭⠹⠱"),
+        ("sup_follow_letter", "⠠⠭⠌⠆⠽"),
+        ("sup_follow_number", "⠠⠭⠌⠆⠼⠉"),
+        ("sub_x", "⠠⠁⠡⠭⠱"),
+        ("sub_zero", "⠠⠭⠡⠴"),
+        ("sub_ten", "⠠⠭⠡⠂⠴"),
+        ("sub_minus_x", "⠠⠁⠡⠀⠤⠭⠱"),
+        ("sub_minus_2", "⠠⠁⠡⠤⠆"),
+        ("sub_x_plus_1", "⠠⠁⠡⠐⠭⠀⠖⠼⠁⠱"),
+        ("sub_nested", "⠠⠁⠡⠭⠡⠆⠱"),
+        ("sub_follow_letter", "⠠⠭⠡⠆⠽"),
+        ("sub_follow_number", "⠠⠭⠡⠆⠼⠉"),
+        ("subsup_numeric", "⠠⠭⠡⠼⠁⠌⠼⠃⠱"),
+        ("subsup_i_n", "⠠⠭⠡⠊⠌⠝⠱"),
+        ("subsup_grouped_sub", "⠠⠭⠡⠐⠊⠀⠖⠼⠁⠌⠼⠃⠱"),
+        ("subsup_grouped_sup", "⠠⠭⠡⠼⠚⠌⠠⠝⠀⠤⠼⠁⠱"),
+        ("subsup_nested_sup", "⠠⠭⠡⠼⠚⠌⠠⠝⠌⠆⠱"),
+        ("negative_base_sup", "⠤⠠⠭⠌⠆"),
+        ("paren_base_sup", "⠣⠠⠭⠀⠖⠼⠁⠜⠌⠆"),
+        ("frac_base_sup", "⠼⠁⠳⠠⠭⠌⠆"),
+        ("root_base_sup", "⠩⠱⠠⠭⠹⠌⠆"),
+        ("sup_on_function", "⠫⠎⠌⠆⠠⠭"),
+        ("log_sub_sup", "⠫⠇⠡⠼⠃⠌⠼⠉⠱⠠⠭"),
+        ("root_index_group", "⠩⠠⠝⠀⠖⠼⠁⠱⠠⠭⠹"),
+        ("root_index_sub", "⠩⠠⠝⠡⠆⠱⠭⠹"),
+        ("frac_num_group", "⠆⠠⠭⠀⠖⠼⠁⠀⠳⠠⠽⠰"),
+        ("frac_den_group", "⠆⠠⠭⠀⠳⠽⠀⠖⠼⠁⠰"),
+        ("nested_frac", "⠆⠆⠼⠁⠀⠳⠠⠭⠰⠀⠳⠆⠼⠁⠀⠳⠠⠽⠰⠰"),
+        ("sup_after_fraction", "⠆⠠⠭⠀⠖⠼⠁⠀⠳⠠⠽⠀⠤⠼⠁⠰⠌⠆"),
+        ("sub_after_fraction", "⠆⠠⠭⠀⠖⠼⠁⠀⠳⠠⠽⠀⠤⠼⠁⠰⠡⠠⠊⠱"),
+        ("tensor_like", "⠨⠞⠡⠠⠊⠌⠚⠱⠭⠡⠚⠌⠅⠱"),
+        ("pre_negative_power", "⠼⠃⠠⠭⠌⠤⠂"),
+        ("power_of_power_follow", "⠠⠭⠌⠆⠌⠒⠽"),
+        ("subscripted_power_follow", "⠠⠭⠡⠆⠌⠒⠽"),
+        ("power_subscript_follow", "⠠⠭⠌⠆⠡⠒⠽"),
+    ]);
+
+    for (label, expr) in cases {
+        test_braille("Russian", expr, expected[label])?;
+    }
+    return Ok(());
+}
+
 #[test]
 fn numbers_and_operators() -> Result<()> {
     let expr = r#"<math><mrow><mn>5</mn><mo>+</mo><mn>12</mn><mo>=</mo><mn>17</mn></mrow></math>"#;