diff --git a/fints4javaLib/src/main/kotlin/net/dankito/fints/response/ResponseParser.kt b/fints4javaLib/src/main/kotlin/net/dankito/fints/response/ResponseParser.kt
index a1fb2f1b..be748b1a 100644
--- a/fints4javaLib/src/main/kotlin/net/dankito/fints/response/ResponseParser.kt
+++ b/fints4javaLib/src/main/kotlin/net/dankito/fints/response/ResponseParser.kt
@@ -167,7 +167,7 @@ open class ResponseParser @JvmOverloads constructor(
         val supportedLanguages = parseLanguages(dataElementGroups[5])
         val supportedHbciVersions = parseHbciVersions(dataElementGroups[6])
 
-        val maxMessageSize = if (dataElementGroups.size > 7) parseInt(dataElementGroups[7]) else null
+        val maxMessageSize = if (dataElementGroups.size > 7) parseIntToNullIfEmpty(dataElementGroups[7]) else null
         val minTimeout = if (dataElementGroups.size > 8) parseInt(dataElementGroups[8]) else null
         val maxTimeout = if (dataElementGroups.size > 9) parseInt(dataElementGroups[9]) else null
 
@@ -680,6 +680,14 @@ open class ResponseParser @JvmOverloads constructor(
         return parseString(string).toInt()
     }
 
+    protected open fun parseIntToNullIfEmpty(string: String): Int? {
+        if (string.isNotEmpty()) {
+            return parseNullableInt(string)
+        }
+
+        return null
+    }
+
     protected open fun parseNullableInt(mayInt: String): Int? {
         try {
             return parseInt(mayInt)
diff --git a/fints4javaLib/src/test/kotlin/net/dankito/fints/response/ResponseParserTest.kt b/fints4javaLib/src/test/kotlin/net/dankito/fints/response/ResponseParserTest.kt
index e5b5576f..a6054d62 100644
--- a/fints4javaLib/src/test/kotlin/net/dankito/fints/response/ResponseParserTest.kt
+++ b/fints4javaLib/src/test/kotlin/net/dankito/fints/response/ResponseParserTest.kt
@@ -312,6 +312,34 @@ class ResponseParserTest : FinTsTestBase() {
         ?: run { Assert.fail("No segment of type BankParameters found in ${result.receivedSegments}") }
     }
 
+    // Baader Bank
+
+    @Test
+    fun parseBankParameters_MaxMessageSizeIsAnEmptyString() {
+
+        // when
+        val result = underTest.parse("HIBPA:3:3:3+0+280:70033100+Baader Bank AG+1+1+300++0+300'")
+
+        // then
+        assertSuccessfullyParsedSegment(result, InstituteSegmentId.BankParameters, 5, 3, 3)
+
+        result.getFirstSegmentById<BankParameters>(InstituteSegmentId.BankParameters)?.let { segment ->
+            assertThat(segment.bpdVersion).isEqualTo(34)
+            assertThat(segment.bankCountryCode).isEqualTo(280)
+            assertThat(segment.bankCode).isEqualTo("10070000")
+            assertThat(segment.bankName).isEqualTo("Deutsche Bank")
+
+            assertThat(segment.countMaxJobsPerMessage).isEqualTo(0)
+            assertThat(segment.supportedLanguages).containsExactly(Dialogsprache.German)
+            assertThat(segment.supportedHbciVersions).containsExactly(HbciVersion.FinTs_3_0_0)
+
+            assertThat(segment.maxMessageSize).isEqualTo(0)
+            assertThat(segment.minTimeout).isNull()
+            assertThat(segment.maxTimeout).isNull()
+        }
+        ?: run { Assert.fail("No segment of type BankParameters found in ${result.receivedSegments}") }
+    }
+
     @Test
     fun parseSecurityMethods() {