diff --git a/rewrite-java-test/src/test/java/org/openrewrite/java/ParenthesizeVisitorTest.java b/rewrite-java-test/src/test/java/org/openrewrite/java/ParenthesizeVisitorTest.java
index 66962628f44..a0eb67a2f79 100644
--- a/rewrite-java-test/src/test/java/org/openrewrite/java/ParenthesizeVisitorTest.java
+++ b/rewrite-java-test/src/test/java/org/openrewrite/java/ParenthesizeVisitorTest.java
@@ -174,6 +174,32 @@ void method() {
         );
     }
 
+    @Test
+    void ternaryAsConditionOrCastOperand() {
+        rewriteRun(
+          java(
+            """
+              class Test {
+                  void method(boolean x, boolean y, boolean z) {
+                      boolean a = (x ? y : z) ? y : z;
+                      Object b = (Object) (x ? y : z);
+                      boolean c = (x ? y : z);
+                  }
+              }
+              """,
+            """
+              class Test {
+                  void method(boolean x, boolean y, boolean z) {
+                      boolean a = (x ? y : z) ? y : z;
+                      Object b = (Object) (x ? y : z);
+                      boolean c = x ? y : z;
+                  }
+              }
+              """
+          )
+        );
+    }
+
     @Test
     void instanceofExpressions() {
         rewriteRun(
diff --git a/rewrite-java-test/src/test/java/org/openrewrite/java/cleanup/SimplifyBooleanExpressionVisitorTest.java b/rewrite-java-test/src/test/java/org/openrewrite/java/cleanup/SimplifyBooleanExpressionVisitorTest.java
index 821285e3011..af779449a77 100644
--- a/rewrite-java-test/src/test/java/org/openrewrite/java/cleanup/SimplifyBooleanExpressionVisitorTest.java
+++ b/rewrite-java-test/src/test/java/org/openrewrite/java/cleanup/SimplifyBooleanExpressionVisitorTest.java
@@ -592,6 +592,108 @@ boolean m4(boolean a, boolean b, boolean c) {
         );
     }
 
+    @Test
+    void nestedTernaryNegation() {
+        rewriteRun(
+          java(
+            """
+              public class A {
+                  boolean m1(boolean a, boolean b, boolean x, boolean y, boolean z) {
+                      return !(a ? b ? x : y : z);
+                  }
+                  boolean m2(boolean a, boolean b, boolean x, boolean y, boolean z) {
+                      return !(a ? x : b ? y : z);
+                  }
+                  boolean m3(boolean a, boolean b, boolean x, boolean y, boolean z) {
+                      return !(a ? !b ? x : y : z);
+                  }
+                  boolean m4(boolean a, boolean b, boolean x, boolean y, boolean z) {
+                      return a ? b ? x : y : z;
+                  }
+              }
+              """,
+            """
+              public class A {
+                  boolean m1(boolean a, boolean b, boolean x, boolean y, boolean z) {
+                      return a ? b ? !x : !y : !z;
+                  }
+                  boolean m2(boolean a, boolean b, boolean x, boolean y, boolean z) {
+                      return a ? !x : b ? !y : !z;
+                  }
+                  boolean m3(boolean a, boolean b, boolean x, boolean y, boolean z) {
+                      return a ? b ? !y : !x : !z;
+                  }
+                  boolean m4(boolean a, boolean b, boolean x, boolean y, boolean z) {
+                      return a ? b ? x : y : z;
+                  }
+              }
+              """
+          )
+        );
+    }
+
+    @Test
+    void negatedTernaryBranchWrappedInParentheses() {
+        rewriteRun(
+          java(
+            """
+              public class A {
+                  boolean m1(boolean a, Object o, boolean c) {
+                      return !(a ? o instanceof String : c);
+                  }
+              }
+              """,
+            """
+              public class A {
+                  boolean m1(boolean a, Object o, boolean c) {
+                      return a ? !(o instanceof String) : !c;
+                  }
+              }
+              """
+          )
+        );
+    }
+
+    @Test
+    void negatedTernaryAsOperandKeepsParentheses() {
+        rewriteRun(
+          java(
+            """
+              public class A {
+                  boolean m1(boolean a, boolean b, boolean c, boolean d) {
+                      return !(a ? b : c) && d;
+                  }
+                  boolean m2(boolean a, boolean b, boolean c, boolean d) {
+                      return !(a ? b : c) ? c : d;
+                  }
+                  boolean m3(boolean a, boolean b, boolean c, boolean d) {
+                      return d ? !(a ? b : c) : d;
+                  }
+                  boolean m4(boolean a, boolean b, boolean c) {
+                      return !!(a ? b : c);
+                  }
+              }
+              """,
+            """
+              public class A {
+                  boolean m1(boolean a, boolean b, boolean c, boolean d) {
+                      return (a ? !b : !c) && d;
+                  }
+                  boolean m2(boolean a, boolean b, boolean c, boolean d) {
+                      return (a ? !b : !c) ? c : d;
+                  }
+                  boolean m3(boolean a, boolean b, boolean c, boolean d) {
+                      return d ? a ? !b : !c : d;
+                  }
+                  boolean m4(boolean a, boolean b, boolean c) {
+                      return a ? b : c;
+                  }
+              }
+              """
+          )
+        );
+    }
+
     @Test
     void differentFieldAccesses() {
         rewriteRun(
diff --git a/rewrite-java/src/main/java/org/openrewrite/java/ParenthesizeVisitor.java b/rewrite-java/src/main/java/org/openrewrite/java/ParenthesizeVisitor.java
index 8bc5c40517c..a547b78b7f9 100644
--- a/rewrite-java/src/main/java/org/openrewrite/java/ParenthesizeVisitor.java
+++ b/rewrite-java/src/main/java/org/openrewrite/java/ParenthesizeVisitor.java
@@ -269,7 +269,12 @@ public J visitTernary(J.Ternary ternary, P p) {
         if (needsParentheses(t, parent.getValue())) {
             return parenthesize(t);
         } else if (parent.getValue() instanceof J.Binary ||
-                   parent.getValue() instanceof J.InstanceOf) {
+                   parent.getValue() instanceof J.InstanceOf ||
+                   parent.getValue() instanceof J.TypeCast) {
+            return parenthesize(t);
+        } else if (parent.getValue() instanceof J.Ternary &&
+                   t.isScope(((J.Ternary) parent.getValue()).getCondition())) {
+            // `a ? b : c ? d : e` groups as `a ? b : (c ? d : e)`, so a ternary condition needs parentheses
             return parenthesize(t);
         }
 
diff --git a/rewrite-java/src/main/java/org/openrewrite/java/cleanup/SimplifyBooleanExpressionVisitor.java b/rewrite-java/src/main/java/org/openrewrite/java/cleanup/SimplifyBooleanExpressionVisitor.java
index 22092471649..44bbaa49c37 100644
--- a/rewrite-java/src/main/java/org/openrewrite/java/cleanup/SimplifyBooleanExpressionVisitor.java
+++ b/rewrite-java/src/main/java/org/openrewrite/java/cleanup/SimplifyBooleanExpressionVisitor.java
@@ -21,6 +21,7 @@
 import org.openrewrite.Tree;
 import org.openrewrite.java.JavaVisitor;
 import org.openrewrite.java.MethodMatcher;
+import org.openrewrite.java.ParenthesizeVisitor;
 import org.openrewrite.java.search.SemanticallyEqual;
 import org.openrewrite.java.tree.*;
 import org.openrewrite.marker.Markers;
@@ -146,6 +147,9 @@ public J visitUnary(J.Unary unary, ExecutionContext ctx) {
 
             if (asUnary.getOperator() == J.Unary.Type.Not) {
                 j = unpackExpression(asUnary.getExpression(), asUnary);
+                if (j instanceof J.Ternary) {
+                    j = ParenthesizeVisitor.maybeParenthesize((Expression) j, getCursor());
+                }
             }
             if (asUnary != j) {
                 j = j.withPrefix(asUnary.getPrefix());
@@ -232,15 +236,13 @@ private Expression maybeNegate(Expression expr) {
         } else if (expr instanceof J.Unary && ((J.Unary) expr).getOperator() == J.Unary.Type.Not) {
             return ((J.Unary) expr).getExpression().withPrefix(expr.getPrefix());
         } else if (expr instanceof J.Ternary) {
+            // The negation of `c ? t : f` is `c ? !t : !f`. Flipping the condition and swapping the
+            // branches instead would preserve the ternary's value rather than negate it.
             J.Ternary ternary = (J.Ternary) expr;
-            Expression negatedCondition = maybeNegate(ternary.getCondition());
-            if (negatedCondition != ternary.getCondition()) {
-                return ternary
-                        .withCondition(negatedCondition)
-                        .withTruePart(ternary.getFalsePart())
-                        .withFalsePart(ternary.getTruePart())
-                        .withPrefix(expr.getPrefix());
-            }
+            return ternary
+                    .withTruePart(maybeNegate(ternary.getTruePart()))
+                    .withFalsePart(maybeNegate(ternary.getFalsePart()))
+                    .withPrefix(expr.getPrefix());
         } else if (isLiteralTrue(expr)) {
             return ((J.Literal) expr).withValue(false).withValueSource("false");
         } else if (isLiteralFalse(expr)) {
@@ -416,9 +418,9 @@ private static J.Unary not(Expression sideRetained) {
             !(sideRetained instanceof J.Parentheses) &&
             !(sideRetained instanceof J.Unary)) {
             sideRetained = new J.Parentheses<>(Tree.randomId(),
-                    Space.EMPTY,
+                    sideRetained.getPrefix(),
                     Markers.EMPTY,
-                    JRightPadded.build(sideRetained));
+                    JRightPadded.build(sideRetained.withPrefix(Space.EMPTY)));
         }
         return new J.Unary(Tree.randomId(),
                 sideRetained.getPrefix(),