The Hostile Environment is a set of policies introduced in 2012 by then Prime Minister Theresa May that makes it illegal for an undocumented migrant to work, rent accommodation, open a bank account or obtain a driver’s licence. These policies also affect the National Health Service (NHS), barring or making it difficult to safely access healthcare. The government has since cultivated a climate of fear and hostility towards the undocumented migrants, restricting their mobility and conducting a high level of urban spatial control. This policy forces regular citizens to be suspicious of each other and turns us all into border guards to a certain degree. The NHS is one of many public services growingly affected by cross-departmental data-sharing arrangements to support Home Office immigration enforcement, which allows Immigration Enforcement teams to request confidential patient information, such as a home address, from patient records held by the NHS. This has detrimental impacts on undocumented migrants accessing the NHS and further degenerates the trust between patients and medical professionals. The impact of the Hostile Environment has created a set of “invisible borders” that were exacerbated during the COVID-19 global pandemic, where most of the migrants are unwilling and too afraid to take the vaccines even if they were permitted to do so. Some were left alone to suffer.  The COVID-19 Vaccine registration process demands all receivers’ personal information and valid NHS numbers. The strictures of this initial process of identification have become the first barrier for many undocumented migrants to receive any vaccinations. The project explores COVID-19 vaccine registration forms as a medium for distributing inequalities and critically reflects on the digitalisation process of registration forms for cross-departmental data-sharing. Exploiting the concept of illegible handwriting and the limits of Optical character recognition (OCR), the project wants to foreground how healthcare can be coopted into a site of discrimination.