diff --git a/Documentation/sophia-net-signalling.md b/Documentation/sophia-net-signalling.md
index 8377648..3b3f2a0 100644
--- a/Documentation/sophia-net-signalling.md
+++ b/Documentation/sophia-net-signalling.md
@@ -6,16 +6,22 @@ the following Signalling applies:
 ## Stream Types in PMT:
 
 |Stream Type|Interpretation						|
+|-----------|-----------------------------------|
 |0x80		|TBS 6903-X GSE Packets				|
 |0x81		|AC-3 Audio							|
 |0x82		|PID only used for PCR				|
+|0x83		|AC-3 True HD Audio                 |
+|0x84       |AC-3+ Audio                        |
+|0x85       |ULE (RFC 4326)                     |
 
 ## Descriptors:
 
 Sophia.net employs the following descriptors:
 
 |Descriptor	|Interpretation							|
+|-----------|---------------------------------------|
 |0x80		|Encapsulated Transport Stream over MPE	|
+|0x81       |Ignore Flags for Skyscraper            |
 
 ### 0x80: Encapsulated Transport Stream over MPE
 When the following conditions all apply:
@@ -27,6 +33,11 @@ THEN: This PID will contain an Encapsulated Transport Stream carried within MPE
 
 Data within this descriptor should be a human readable description of what the Encapsulated Transport Stream is, but can be left empty.
 
+### 0x81: Ignore Flags for Skyscraper
+This descriptor is allowed in all tables and is exactly one byte long.
+When this descriptor is present, skyscraper8 will not be writing any sort of data in the current table into it's Data Storage.
+However, if this descriptor appears in an outer table of a PMT, skyscraper8 will still scan the PIDs, and attach parsers to it, but won't write them to it's Data Storage.
+
 
 ## Other Rules: