diff --git a/README.md b/README.md
index be2c0125..abaa06e3 100644
--- a/README.md
+++ b/README.md
@@ -146,4 +146,40 @@ A valid JSON object can look like this:
         "tumor": "no"
     }
 }
-```
\ No newline at end of file
+```
+
+### Attachment Data
+
+**Responsible dropbox:**
+[QBiC-register-exp-proj-attachment](drop-boxes/register-attachments-dropbox)
+
+**openBIS structure:**
+
+Attachments are attached to the Q_PROJECT_DETAILS experiment type and its sample type Q_ATTACHMENT_SAMPLE.
+
+**Expected data structure**
+The data structure needs to be a root folder, containing a file `metadata.txt`.
+
+Incoming structure overview:
+
+```
+|-<anything> (top level folder name, normally a time stamp of upload time)
+    |
+    |- metadata.txt
+```
+
+**Expected metadata**
+Metadata is expected to be denoted in line-separated key-value pairs, where key and value are separated by a '='. The following structure/pairs are expected:
+
+```
+user=<the (optional) uploading user name>
+info=<short info about the file>
+barcode=<the sample code of the attachment sample>
+type=<the type of attachment: information or results>
+```
+The code of the attachment sample is built from the project code followed by three zeroes, conforming to the regular expression "Q[A-Z0-9]{4}000", e.g. QABCD000.
+
+See code examples:
+https://github.com/qbicsoftware/attachi-cli/blob/master/attachi/attachi.py#L63
+https://github.com/qbicsoftware/projectwizard-portlet/blob/9c86f500b26af4cf2613cfae32e470bf5d50bf78/src/main/java/life/qbic/projectwizard/io/AttachmentMover.java#L145
+
diff --git a/drop-boxes/register-attachments-dropbox/register-attachment-dropbox.py b/drop-boxes/register-attachments-dropbox/register-attachment-dropbox.py
index cd82f564..27abd34c 100755
--- a/drop-boxes/register-attachments-dropbox/register-attachment-dropbox.py
+++ b/drop-boxes/register-attachments-dropbox/register-attachment-dropbox.py
@@ -92,18 +92,6 @@ def process(transaction):
 		sa.setExperiment(exp)
 	info = None
 
-	#if isProject:
-	#experiments = search_service.listExperiments("/" + space + "/" + project)
-	#for e in experiments:
-	#	if project+"_INFO" in e.getExperimentIdentifier():
-	#		info = e
-	#if not info:
-	#	info = transaction.createNewExperiment('/' + space + '/' + project + '/'+ project+'_INFO', "Q_PROJECT_DETAILS")
-	#else:
-	#	info = transaction.getExperiment('/' + space + '/' + project + '/' + code)
-	# register new experiment and sample
-	#sa.setExperiment(info) 
-	# create new dataset 
 	dataSet = transaction.createNewDataSet("Q_PROJECT_DATA")
 	dataSet.setMeasuredData(False)
 	dataSet.setPropertyValue("Q_SECONDARY_NAME", secname)