# 1M multi-lingual synthetic corporate emails to stress-test your RAG > Source: > Published: 2026-10-12 09:32:25+00:00 [Duplicate](https://huggingface.co/datasets/sinabis-group/sinabis-1m-synthetic-emails?duplicate=true) ## The dataset viewer is not available for this split. ``` Error code: FeaturesError Exception: ArrowInvalid Message: JSON parse error: Invalid value. in row 0 Traceback: Traceback (most recent call last): File "/usr/local/lib/python3.14/site-packages/datasets/packaged_modules/json/json.py", line 324, in _generate_tables df = pandas_read_json(f) File "/usr/local/lib/python3.14/site-packages/datasets/packaged_modules/json/json.py", line 38, in pandas_read_json return pd.read_json(path_or_buf, **kwargs) ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^ File "/usr/local/lib/python3.14/site-packages/pandas/io/json/_json.py", line 815, in read_json return json_reader.read() ~~~~~~~~~~~~~~~~^^ File "/usr/local/lib/python3.14/site-packages/pandas/io/json/_json.py", line 1014, in read obj = self._get_object_parser(self.data) File "/usr/local/lib/python3.14/site-packages/pandas/io/json/_json.py", line 1040, in _get_object_parser obj = FrameParser(json, **kwargs).parse() File "/usr/local/lib/python3.14/site-packages/pandas/io/json/_json.py", line 1176, in parse self._parse() ~~~~~~~~~~~^^ File "/usr/local/lib/python3.14/site-packages/pandas/io/json/_json.py", line 1392, in _parse ujson_loads(json, precise_float=self.precise_float), dtype=None ~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ValueError: Expected object or value During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/src/services/worker/src/worker/job_runners/split/first_rows.py", line 244, in compute_first_rows_from_streaming_response iterable_dataset = iterable_dataset._resolve_features() File "/usr/local/lib/python3.14/site-packages/datasets/iterable_dataset.py", line 4523, in _resolve_features features = _infer_features_from_batch(self.with_format(None)._head()) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^ File "/usr/local/lib/python3.14/site-packages/datasets/iterable_dataset.py", line 2768, in _head return next(iter(self.iter(batch_size=n))) File "/usr/local/lib/python3.14/site-packages/datasets/iterable_dataset.py", line 2972, in iter for key, pa_table in ex_iterable.iter_arrow(): ~~~~~~~~~~~~~~~~~~~~~~^^ File "/usr/local/lib/python3.14/site-packages/datasets/iterable_dataset.py", line 2483, in _iter_arrow yield from self.ex_iterable._iter_arrow() File "/usr/local/lib/python3.14/site-packages/datasets/iterable_dataset.py", line 547, in _iter_arrow for key, pa_table in iterator: ^^^^^^^^ File "/usr/local/lib/python3.14/site-packages/datasets/iterable_dataset.py", line 430, in _iter_arrow for key, pa_table in self.generate_tables_fn(**gen_kwags): ~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^ File "/usr/local/lib/python3.14/site-packages/datasets/packaged_modules/json/json.py", line 327, in _generate_tables raise e File "/usr/local/lib/python3.14/site-packages/datasets/packaged_modules/json/json.py", line 290, in _generate_tables pa_table = paj.read_json( io.BytesIO(batch), read_options=paj.ReadOptions(block_size=block_size) ) File "pyarrow/_json.pyx", line 364, in pyarrow._json.read_json File "pyarrow/error.pxi", line 155, in pyarrow.lib.pyarrow_internal_check_status File "pyarrow/error.pxi", line 92, in pyarrow.lib.check_status raise convert_status(status) pyarrow.lib.ArrowInvalid: JSON parse error: Invalid value. in row 0 ``` Need help to make the dataset viewer work? Make sure to review [how to configure the dataset viewer](https://huggingface.co/docs/hub/datasets-data-files-configuration), and [open a discussion](https://huggingface.co/datasets/sinabis-group/sinabis-1m-synthetic-emails/discussions/new?title=Dataset+Viewer+issue%3A+FeaturesError&description=The+dataset+viewer+is+not+working.%0A%0AError+details%3A%0A%0A%60%60%60%0AError+code%3A+++FeaturesError%0AException%3A++++ArrowInvalid%0AMessage%3A++++++JSON+parse+error%3A+Invalid+value.+in+row+0%0ATraceback%3A++++Traceback+%28most+recent+call+last%29%3A%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fdatasets%2Fpackaged_modules%2Fjson%2Fjson.py%22%2C+line+324%2C+in+_generate_tables%0A++++++++++++++++++df+%3D+pandas_read_json%28f%29%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fdatasets%2Fpackaged_modules%2Fjson%2Fjson.py%22%2C+line+38%2C+in+pandas_read_json%0A++++++++++++++++++return+pd.read_json%28path_or_buf%2C+**kwargs%29%0A+++++++++++++++++++++++++%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fpandas%2Fio%2Fjson%2F_json.py%22%2C+line+815%2C+in+read_json%0A++++++++++++++++++return+json_reader.read%28%29%0A+++++++++++++++++++++++++%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%5E%5E%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fpandas%2Fio%2Fjson%2F_json.py%22%2C+line+1014%2C+in+read%0A++++++++++++++++++obj+%3D+self._get_object_parser%28self.data%29%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fpandas%2Fio%2Fjson%2F_json.py%22%2C+line+1040%2C+in+_get_object_parser%0A++++++++++++++++++obj+%3D+FrameParser%28json%2C+**kwargs%29.parse%28%29%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fpandas%2Fio%2Fjson%2F_json.py%22%2C+line+1176%2C+in+parse%0A++++++++++++++++++self._parse%28%29%0A++++++++++++++++++%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%5E%5E%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fpandas%2Fio%2Fjson%2F_json.py%22%2C+line+1392%2C+in+_parse%0A++++++++++++++++++ujson_loads%28json%2C+precise_float%3Dself.precise_float%29%2C+dtype%3DNone%0A++++++++++++++++++%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%0A++++++++++++++ValueError%3A+Expected+object+or+value%0A++++++++++++++%0A++++++++++++++During+handling+of+the+above+exception%2C+another+exception+occurred%3A%0A++++++++++++++%0A++++++++++++++Traceback+%28most+recent+call+last%29%3A%0A++++++++++++++++File+%22%2Fsrc%2Fservices%2Fworker%2Fsrc%2Fworker%2Fjob_runners%2Fsplit%2Ffirst_rows.py%22%2C+line+244%2C+in+compute_first_rows_from_streaming_response%0A++++++++++++++++++iterable_dataset+%3D+iterable_dataset._resolve_features%28%29%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fdatasets%2Fiterable_dataset.py%22%2C+line+4523%2C+in+_resolve_features%0A++++++++++++++++++features+%3D+_infer_features_from_batch%28self.with_format%28None%29._head%28%29%29%0A++++++++++++++++++++++++++++++++++++++++++++++++++++++++%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%5E%5E%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fdatasets%2Fiterable_dataset.py%22%2C+line+2768%2C+in+_head%0A++++++++++++++++++return+next%28iter%28self.iter%28batch_size%3Dn%29%29%29%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fdatasets%2Fiterable_dataset.py%22%2C+line+2972%2C+in+iter%0A++++++++++++++++++for+key%2C+pa_table+in+ex_iterable.iter_arrow%28%29%3A%0A+++++++++++++++++++++++++++++++++++++++%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%5E%5E%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fdatasets%2Fiterable_dataset.py%22%2C+line+2483%2C+in+_iter_arrow%0A++++++++++++++++++yield+from+self.ex_iterable._iter_arrow%28%29%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fdatasets%2Fiterable_dataset.py%22%2C+line+547%2C+in+_iter_arrow%0A++++++++++++++++++for+key%2C+pa_table+in+iterator%3A%0A+++++++++++++++++++++++++++++++++++++++%5E%5E%5E%5E%5E%5E%5E%5E%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fdatasets%2Fiterable_dataset.py%22%2C+line+430%2C+in+_iter_arrow%0A++++++++++++++++++for+key%2C+pa_table+in+self.generate_tables_fn%28**gen_kwags%29%3A%0A+++++++++++++++++++++++++++++++++++++++%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%7E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%5E%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fdatasets%2Fpackaged_modules%2Fjson%2Fjson.py%22%2C+line+327%2C+in+_generate_tables%0A++++++++++++++++++raise+e%0A++++++++++++++++File+%22%2Fusr%2Flocal%2Flib%2Fpython3.14%2Fsite-packages%2Fdatasets%2Fpackaged_modules%2Fjson%2Fjson.py%22%2C+line+290%2C+in+_generate_tables%0A++++++++++++++++++pa_table+%3D+paj.read_json%28%0A++++++++++++++++++++++io.BytesIO%28batch%29%2C+read_options%3Dpaj.ReadOptions%28block_size%3Dblock_size%29%0A++++++++++++++++++%29%0A++++++++++++++++File+%22pyarrow%2F_json.pyx%22%2C+line+364%2C+in+pyarrow._json.read_json%0A++++++++++++++++File+%22pyarrow%2Ferror.pxi%22%2C+line+155%2C+in+pyarrow.lib.pyarrow_internal_check_status%0A++++++++++++++++File+%22pyarrow%2Ferror.pxi%22%2C+line+92%2C+in+pyarrow.lib.check_status%0A++++++++++++++++++raise+convert_status%28status%29%0A++++++++++++++pyarrow.lib.ArrowInvalid%3A+JSON+parse+error%3A+Invalid+value.+in+row+0%0A%60%60%60%0A%0A%0Acc+%40lhoestq+%40cfahlgren1.) for direct support. # Sinabis Oil – Synthetic Email Dataset More than **1.25 million emails** from the everyday business of a fictional energy company. They span eight and a half years and four languages, and they include real attachments and calendar invitations. Every person, company and event is made up. The content was written by large language models, and the `demo-gen` generator built the structure around it. All figures in this file were **computed from the files themselves** (as of 1 Oct 2026). They are not target values from the configuration. ## At a glance | Emails | **1,251,102** (13.1 GB,`.eml` per RFC 5322) | | Business cases | **376,417** : 262,776 email threads and 113,641 single emails | | Meetings | **9,470** meetings with 45,483 calendar emails, plus 3,020 standalone`.ics` files | | Document attachments | **57,890** : 33,467 PDF · 13,485 DOCX · 10,938 XLSX | | Time span | January 2018 to July 2026, about 146,000 emails per year | | Languages | English, German, French, Italian | | People | 140 employees in 15 departments, 60 external contacts | | Organisations | 1 main company + 39 others (group companies, suppliers, authorities, customers) | ## What it is about **Sinabis Oil & Gas GmbH** (Wilhelmshaven, Germany, fictional) runs drilling operations in the North Sea, a refinery, pipelines and tank farms. The emails show the day-to-day business of such an operation. There are **29 topics**, including: North Sea drilling campaign · refinery turnaround · pipeline inspection · HSE incident report · IT security incident · data protection case · audit · supplier tender · CAPEX budget · shift planning · environmental permit · offshore emergency power · HR topics and more. About 12 % of the emails are private or informal exchanges between colleagues. Single emails are newsletters, memos, circulars, payment reminders and maintenance notices. ### Who is writing? | Group | Count | Examples | |---|---|---| | Sinabis Oil & Gas GmbH | 140 people, 15 departments | E&P, Drilling, Refinery, HSE, Procurement, IT, Legal/Compliance | | Sinabis group companies | 21 | Sinabis Logistik, Sinabis Finanzdienst, Sinabis Consulting | | Suppliers and service providers | 11 | Nordsee Rig Services, Baltic Drilling Supplies, Friesland Inspection | | Authorities | 4 | Landesbergamt Nord, Hafenbehörde Wattkant, Umweltagentur Küstenland | | Energy customers | 3 | Ostsee Stromwerk, Nordlicht Kraftwerke, Küstenstadt Wärme | Activity is **unevenly distributed**, like in a real mailbox: about 145 internal senders write 99 % of the internal emails, some of them tens of thousands each. People only appear during their period of employment. ## Language distribution The language of each email was determined from its subject and its own text, without the quoted history, using stop-word detection. Very short texts, such as calendar replies like "Accepted: …" or "Zugesagt: …", were assigned by their subject line. | Language | Main set | Earlier set | **Total** | **Share** | |---|---|---|---|---| | English | 481,765 | 199,677 | **681,442** | **54.5 %** | | German | 306,392 | 32,991 | **339,383** | **27.1 %** | | French | 102,762 | 26,694 | **129,456** | **10.3 %** | | Italian | 97,069 | 3,752 | **100,821** | **8.1 %** | | **Total** | 987,988 | 263,114 | **1,251,102** | | Every email is **monolingual**: subject, body, signature, disclaimer, legal notice and history header are all in the same language. **Attachments by language** | | | DOCX | XLSX | |---|---|---|---| | English | 20,021 | 6,690 | 5,323 | | German | 7,965 | 4,084 | 3,482 | | French | 3,365 | 1,352 | 1,128 | | Italian | 2,116 | 1,359 | 1,005 | ## Models used In the main set, the tag at the end of the file name (`…-V1.eml`, `…-QW.eml`) shows which model wrote the email. | Tag | Model | Emails | Share | |---|---|---|---| | `V1` –`V6` | Qwen3.6-35B-A3B (AWQ, 4-bit) | 781,765 | 62.5 % | | *(none)* | DeepSeek V4 Flash (no thinking), incl. all 263,114 of the earlier set | 335,068 | 26.8 % | | `QW` | Qwen 3.6 | 88,786 | 7.1 % | | *(none)* , calendar | **no LLM** , rule-based | 45,483 | 3.6 % | The PDF, DOCX and XLSX attachments are real files. The model only supplies the content; the generator builds the files itself. ## Downloads The dataset is split into archives so you only need to download what you're interested in: | Archive | Contents | |---|---| | `Sinabis_Demo_Dataset_emails.zip` | 1,251,102 `.eml` files | | `Sinabis_Demo_Dataset_chats.zip` | chat/messenger conversations | | `Sinabis_Demo_Dataset_appointments.zip` | standalone `.ics` calendar files | Each archive keeps the internal folder structure shown below. `README.md` and `docs/` are plain files in the repo, not zipped. ## Folder structure ``` . ├── README.md ├── docs/ │ └── generation/ │ ├── prompts.json │ ├── chat_prompts.json │ └── company.json ├── Sinabis_Demo_Dataset_emails.zip │ └── batch-0001 … batch-0031/ ├── Sinabis_Demo_Dataset_chats.zip │ └── batch-0001 … batch-0002/ └── Sinabis_Demo_Dataset_appointments.zip ``` The batch folders only split the data so that no single folder holds a million files. They carry no meaning. ## How everything is linked ### Email threads ``` --.eml │ │ └─ model (see above), missing for DeepSeek and calendar │ └────── position in the thread (01, 02, …) └────────────────── SHA-256 over the whole thread, same for all its emails ``` - All emails of one case share the **same file name prefix** . - The headers link the emails: `Message-ID` ,`In-Reply-To` and`References` each point to the previous email. - Every email contains the **quoted history** (`> …` ) of all earlier emails, so a single file already shows the whole thread. - 99 % of threads have **3 to 6 emails** . ### Attachments - Attachments are **embedded in the email** (MIME, Base64), not stored as separate files next to it. - The document is the **source the email refers to** , for example an inspection report or a budget sheet, not a copy of the email text. It has the same language and the same date as the email. ### Meetings - A meeting consists of **several emails with an `.ics` attachment** : the invitation (`REQUEST` ) to all attendees, acceptances or declines (`REPLY` ) to the organiser, and possibly a cancellation (`CANCEL` ). - These emails share the same file name prefix. 9,470 meetings produce 45,483 calendar emails this way. - The standalone `.ics` files in`Sinabis_Demo_Dataset_appointments.zip` are meetings without an email (`appt___