Dataharvest 2026 - the European Investigative Journalism Conference

Over the past three years, the Guardian Data Projects team has revealed how private equity firms have increased their share in the childcare sector as well as in the provision of children’s care homes in England. We have also investigated how taxpayers’ money for services that provide support for rape and sexual assault victims ends up in private equity companies. And we have estimated that the UK government has spent billions of pounds in companies that are owned by a private equity group.

Attendees to this session will learn about two methodologies the Guardian built to track down the involvement of private equity firms in the country’s economy and specific sectors. They will also learn about specific resources to find out company data, as well as understand how the Guardian built an automated system to analyse thousands of company records to find the ultimate controlling party for each company group. We will also show how an LLM helped to identify companies owned by a private equity firm, as well as the limitations of using this type of technique.

In almost all research, we need to uncover information about given individuals: criminals, extremists, corrupt public officials. This workshop focuses on identifying the players in a nasty game, as well as people who can provide valuable information as sources. It delves into investigating their social media accounts, their addresses, and their networks. Details they aim to keep hidden but often fail to.

We will provide strategies, tools and tricks for finding people online. What can email addresses, social media profiles and telephone numbers reveal about a person? How can data leaks, Google reviews, and even apps like Strava offer insights for research? And what do the deceased leave behind? We go beyond abstract methods and present real-world investigation cases: Learn how an investigation can start with nothing more than a name – and end with ringing someone’s doorbell.

The examples include investigations into neo-Nazis and other extremists, police officers and unpeaceful UN peacekeepers, criminal divers, and Secret Service agents kidnapping people.

Everyone listens to audio all the time, yet investigators rarely think of it. This session introduces audio forensics as an often-overlooked OSINT skill. We’ll explore how frequencies, compression, spectrograms, and a touch of physics can be used to authenticate media, detect edits, determine locations, and even prove war crimes. Participants will learn how to calculate a shooter’s distance using bullet speed and the speed of sound, analyse electrical network frequencies, and recognise platform-specific compression. No prior experience in OSINT or extensive knowledge of audio is required — this session is suitable for beginners.

Public archives all over the continent are full of historical stories waiting to be told. From armed conflict and genocide to colonialism or the environment, there are enough subjects that are still very relevant for investigative journalism.

This session will focus on the challenges and, more importantly, the possibilities of working with on-paper archives and analogue photographs. Is it possible to geolocate old prints without metadata or StreetView? Are there any old-school tricks to verify images? And what about AI slop that disguises itself as historical material?

We'll also discuss the importance of historical investigative work, possible subject areas, and useful tools and resources. The session is meant to inspire investigative journalists to dive headfirst into public archives and find relevant stories using their existing skills.

This session will cover how to use trade information for investigative reporting, from the theory behind commercial flows to its application to real investigative cases. The first part of the presentation will focus on the "dictionary" that is crucial to read and interpret trade data. Then, it will explore how to source official customs statistics for free, understand crucial variables in import-export sheets, and find workarounds to expensive third-party commercial providers.

Examples from real investigations will show the power of using trade data in covering topics such as deforestation, sanctions evasion, the military industry, cocaine trafficking, but also much more "ordinary" commercial flows that might be linked to pollution/environmental issues. Throughout the session, participants will be welcome to bring examples of commodities they would like to track and guided in a few hands-on exercises to familiarise themselves with finding and understanding this kind of data.

The session is suitable for beginners. No technical/coding experience is needed, but the participants should be familiar with spreadsheets.

AI-generated scam advertisements have flooded European social media platforms, using deepfake videos, cloned voices, and fabricated news stories to lure thousands of victims into fraudulent investment schemes. While the EU's Digital Services Act (DSA) was designed to curb illegal and harmful content, these scams continue to spread at scale, exposing major gaps in platform enforcement and regulatory oversight.

This session will show how to investigate AI-driven scam ads and platform failure using publicly available tools, leaked material, and EU tech legislation. We will walk through how to find and identify and analyse AI-generated scam ads and deepfake content, use Meta's Ad Library to map scam campaigns, detect duplication and evasion tactics, and estimate scale. The session will also address how to collaborate effectively with civil society organisations and trusted flaggers to monitor platforms and access specialised expertise.

As part of the presentation, we'll also talk about how to investigate the Digital Services Act in practice, including transparency obligations, systemic-risk provisions and reporting mechanisms; how to document and report on failures of enforcement by platforms and public authorities, and how to connect platform-level analysis to human stories, including victims' experiences. That also includes how to responsibly handle leaked messages, call scripts, and fake trading platforms, balancing verification, security and ethical considerations.

The session will include concrete examples and live walkthroughs, showing how journalists can combine platform data, legal frameworks and human sources to hold tech companies and regulators accountable. 

Predictive Markets are on the rise, and with them, easy money for insider knowledge and those who can influence their outcomes. While regulation is slow to catch up, investigations don't have to be. Polymarket is the most well-known of these predictive markets, and one thing that defines it is open data on all exchanges going on in a market.

This session will cover key concepts of Polymarket and the possibilities and limitations of investigating it. It will include basic Python code to extract and analyse its open data, and a new open source user interface tool you can use to quickly understand the market and accounts. In the end, we will learn techniques to identify suspicious actors from a few example markets.

Although some code will be shared during the session, you don't need to have a working knowledge of Python to participate.

In our digitally connected world, perpetrators feel so safe online that they build their networks openly: on public-access porn websites and messenger apps such as Telegram. Our investigation for STRG_F/NDR in Germany uncovered an international rape network that had formed on porn websites and in dozens of private chat groups on Telegram. One group had more than 70,000 members.

Users exchange detailed information on how to drug and rape women who are already close to them, such as their wives, girlfriends, sisters, or mothers, without them noticing. The rapists share videos and photos of the assaults online. One man from Germany drugged and raped his wife for more than 15 years and generated millions of views with the footage. Our investigation triggered a police investigation, and he was stopped.

We'll share how we began investigating these networks, how we gained access to them, how we investigated the users for years by also going undercover, what tools we used, what ethical and moral challenges we have faced, and how we kept an overview of all the footage we documented and saved over the years.

We will address:
- How do you conduct online research in criminal networks? (Structures, dynamics, and mechanisms)
- How do you gain access to them?  (User's communication and behaviour) 
- What opportunities and limitations did we encounter? (Laws and journalists' rights, ethical and moral responsibilities)
- When should you consider undercover research, and what can it look like? (Journalistic standards and guidelines)
- How do you protect your own mental health when confronted with disturbing content?

Following Russia's invasion of Ukraine, many European countries have increased their defence spending and awarded large new contracts to arms companies. Beneficiaries include US corporations such as Lockheed, as well as European firms such as BAE Systems, Airbus, Rheinmetall, or Leonardo. At the same time, these companies are making money by exporting weapons to authoritarian regimes, and their weapons could end up on the battlefields of Libya or Yemen. Some of these companies have continued to support Israel in its destruction of Gaza by selling weapons to the country.
How can such companies be investigated? Whistleblowers can occasionally help journalists to expose dubious deals and hidden manoeuvres. But arms deals can also be investigated without the help of an insider. Videos showing military vehicles can be geolocated. Satellite pictures reveal the locations of naval vessels. Tracking websites allow you to follow the routes of warships and aeroplanes. Company employees reveal the military projects they are working on on LinkedIn.

This presentation will demonstrate how open-source methods can be used to investigate the arms industry. Drawing on specific examples from recent investigations, it will show how these methods can be employed to shed light on the activities of companies such as a European missile-maker that supplied Israel with bombs used in Gaza, German engine manufacturers whose products are being used in Russian and Chinese warships, Turkey's breaches of the arms embargo in Libya, and the role of Airbus, as well as French-made warships in the war zone around Yemen. The presentation will also highlight the activities of a German arms giant Rheinmetall,, which sent personnel through an embargoed port in Eritrea to assist with the repair of Emirati naval guns in the Red Sea.

The Great Firewall, censorship, and language barriers make open source research on China really difficult, if not impossible. In this session, we aim not only to make you aware of obstacles you may face, but to show you solutions and strategies, especially for journalists and researchers working from outside China who don't speak the language.

We’ll show you the research resources, toolbox and we'll share tips on:

1) how to navigate Chinese social media: WeChat, Douyin, Rednote and others,
2) how to reconcile information inconsistencies in English and Chinese,
3) how to read the ownership of Chinese companies: private, state owned and central government enterprises,
4) mobile device setup and translation applications.

Do you know what the telling signs of "non-authentic behaviour" - bots - are on social media platforms? This practical, hands-on presentation is for journalists interested in investigating bots across platforms - from Telegram and YouTube to TikTok. We'll use data research on bot networks and coordinated activity to learn how to identify bots, and discuss practical stories one can develop based on the data found. We will also give practical examples stemming from our research in Ukraine and Moldova, and present some insights into bot campaigns ahead of the June 2026 election in Armenia.

A key part of the session will focus on how things are changing with the rise of generative AI and the early shift toward more agent-like systems: what this means for bots, coordination, and the limits of traditional detection methods. By the end of the workshop, participants will have a clearer sense of how large-scale CIB operations can look in practice, and how to start identifying and documenting them across different platforms. The goal is to leave the session with concrete story ideas, investigative ideas, and practical methodological knowledge.

No programming skills are required to take part in the workshop, but prior experience with collecting and analyzing data from social media platforms will help participants get the most out of the session.

Everyone knows that you can track planes online. But how exactly do you use plane tracking tools, and how can they help you with investigative research in particular? That's what this workshop is all about. It's aimed at journalists who have only ever tracked their vacation flights, but it also offers tips and tricks for more experienced colleagues. (It can get a little nerdy at times, but hopefully never boring.)

This session will tackle questions such as:
-How do you use flight tracking sites for research?
-Can you really track all planes? And what do you do if they don't want a flight to be found?
-What are the advantages and disadvantages of different platforms?
-How does flight data help to verify other information from your research?
-What are the biggest stumbling blocks, and what do you need to watch out for?
-How do you access older data?
-And why are plane spotters your best friends...

The tools of the trade are explained with practical examples from real research cases. These include Russian sabotage and hijackings, kings on their travels, and smuggled wild animals.

Industry biases science by funding research projects and organisations, as well as individual scientists. In this session, we will explore how to investigate this bias, presenting different approaches, story angles, data sources, and methods. We will focus on investigations covering food, tobacco, environment, and medicine. The attendees will get an understanding of the importance of commercial influence on science, ways to investigate the subject, as well as possible pitfalls. 

Analysts estimate that at least $28 billion tied to illicit activity has flowed into cryptocurrency exchanges over the last two years. ICIJ's Coin Laundry investigation, in collaboration with 37 media partners, exposed part of this shadow financial system, collecting dozens of cryptocurrency wallet addresses and uncovering hundreds of millions of dollars' worth of illicit funds linked to suspected criminals, including a Cambodian conglomerate that facilitated money laundering for hackers and scam compound operators.

In this hands-on session, the panelists will explain how any reporter can use open source resources as well as advanced techniques to investigate major crypto exchanges, find leads, and "follow the crypto." The session will blend an intro showing the kinds of stories you can do on crypto, starting from scratch, the kinds of tools you can use, and then show how we use those tools to compile the data for analysis.

Algorithms are everywhere, but they're still extremely opaque. They affect us more and more, and often have a meaningful impact on our daily lives—especially when the public administration uses them. But it's incredibly hard to 1) get data and information about how they work, 2) understand it, and 3) explain it in a simple, impactful way.

In this session, we'll share different techniques that Civio has used to research and report on algorithms. We'll look into the ways in which one can crack open the black box of algorithms, from FOIA requests to court battles, reverse engineering to scientific reports. We will also explain how we analyse their outputs and how we make reporting that is often technical and complex more palatable for our readers. In the presentation, we will mention some particular examples from our reporting on algorithms, such as exposing facial recognition in doctor offices, algorithm bias when it comes to cancer detection, and a silly lie detector used by police.

We'll also talk about how we went to the Supreme Court to get the code of a system which decides -wrongly- who receives subsidies, and who doesn't. This session is suitable for beginners - you don't need to have had any experience reporting on algorithms in order to attend and follow the session.

Investigace.cz has been monitoring TikTok in the Czech Republic for foreign influence operations for several years. and has learned to track the Czech TikTok space systematically.

In this hands-on session, they will share the lessons learnt with the participants:

-How to use scraping-as-a-service tools to collect TikTok data without coding
-How to decode TikTok URL hashes to extract hidden metadata (such as exact publication timestamps)
-How to work with the TikTok Research API
-How to think beyond simple metrics (views, likes, followers) and understand what TikTok data can and cannot tell you about influence operations

Participants will leave with practical skills and a realistic understanding of the limits of TikTok analysis. One doesn't need to be a data journalist to attend this session, but an understanding of how scraping works and basic data skills will be helpful!

Much of modern life is mediated through phones and apps. To investigate anything they touch, you need to understand where these apps' data comes from, what they're sharing, and with whom. But while network forensics & scraping for the web have received plenty of attention, the same isn't true for mobile, where techniques can be more challenging and clear guides are harder to find.

In this talk, we'll take a hands-on look at how HTTP Toolkit and other tools make it possible to easily capture, inspect & modify network traffic on mobile. We'll explore real-world examples of these techniques in data journalism, and you'll learn how you can use this to extract the datasets that power mobile apps, expose privacy leaks & security issues, and investigate exactly how apps do what they do.

This session is based on a case from Serbia, where we managed to identify a person whose identity Serbian authorities and pro-government media actively tried to hide. Starting from a blurred face in a leaked video, we combined basic OSINT with business registries, social networks, geolocation, face recognition tools, dark web email searches, and simple AI-assisted image analysis. We will walk the audience through each phase of the process,  and explain what worked, what failed, and how one can verify findings when evidence is being altered or erased in real time.

Attendees will leave with a practical workflow they can reuse in their own investigations: how to move from a fragment of visual evidence to a confirmed identity, how to cross-check business data with social platforms, how to use face search and morphological comparison safely, how to track digital behavior after supposed arrests, and how to document disappearing online traces before they are wiped. The goal is to share a method that can travel across borders and work in any country where power structures try to keep people invisible.

According to the OECD, 79% of companies use algorithmic management tools to automate recruitment, manage human resources and, above all, monitor and control workers. Subjected to constant algorithmic surveillance, salespeople in all sectors are always aware that their every move is being scrutinized. In digital professions, particularly video game
design, this digital activity tracking fuels burnout and workplace suffering. Delivery workers, especially those on bicycles, face even more serious consequences: the accelerated pace of their work leads to serious workplace accidents and even death. In France, the press has documented more than twenty fatal accidents since the arrival of Uber 
Eats and Deliveroo to the market in 2015.

How are these technologies deployed? How can we bypass corporate communications to document their real impact? How can we identify the hundreds of small businesses worldwide that market these devices? In this session, Clément Pouré, who has published around fifty investigations on workplace surveillance in the Age of AI, and a book on the same topic, will shed light on the surveillance practices of numerous multinationals such as McDonald's and TP (a world leader in call centers), but also on the more insidious practices of smaller companies across all sectors.

In this session, we'll briefly look into the history of workplace surveillance and its impact on employees, and chart an overview of the current technologies and the risks they represent. We will review the methods and sources that can be used to investigate the subject. The session is suitable for beginners, and no prior experience in algorithmic investigations is required to attend.