A: Great question, here is some background:

Sinosend was originally developed to solve the challenges of transferring large files securely between Hong Kong and Mainland China—hence the “Sino” in our name. Small businesses and larger enterprises struggled to send files across borders efficiently, and we provided a solution to address this specific pain point.

Since then, we’ve grown into a global file transfer service with customers around the world (with the possible exceptions of North Korea and Antarctica!). However, we’re still a small team, and AppSumo has given us the opportunity to reach more users and refine our focus. With that context, let me address your concerns regarding Availability, Integrity, and, most importantly, Confidentiality.

Availability is less about government access to data and more about our redundancy and backup mechanisms. While we don’t currently advertise a formal SLA your data is stored in three separate zones within our operating region. This ensures that if one zone fails, your data will remain accessible through redundancy measures. We take this responsibility seriously and have implemented robust systems to minimize downtime or data loss.

Integrity ensures that your data remains unchanged during transfer or storage. If Bob sends a message to Alice, how can Alice know the message has not been manipulated by a man in the middle? We solve this by using hashing and encryption technologies. For instance, an MD5 hash is calculated for your file, ensuring that if the data were tampered with during transit, the hashes would no longer match.
Similarly, encryption ensures that even if a file is intercepted or tampered with en route, it would not be readable without the decryption key.
This safeguards your data from unauthorized modifications, ensuring that what you send is exactly what your recipient receives.

Confidentiality. this is the core of your question and understandably a concern for anyone transferring data. Here’s how we address confidentiality:

You referenced the 2017 China Data Security Law and the assumption that data in Hong Kong would automatically fall under Mainland China’s jurisdiction. However, it’s important to clarify:

Hong Kong operates under a separate legal system. The Personal Data (Privacy) Ordinance (PDPO) governs data privacy in Hong Kong, and it does not mandate the disclosure of data to Mainland China. Hong Kong data users are not required to hand over data to Mainland authorities unless there is a specific legal basis, such as a cross-border agreement or something more substantial then a business to business file transfer service. Moreover, we do not store any data in Mainland China. Data may only be transferred to China if your intended recipient is located there, and even then, the data is typically ephemeral.

Tanner DeWitt a internaitoinal law firm has an interesting video on this https://www.tannerdewitt.com/data-transfers-involving-hong-kong/

As with any jurisdiction, we are obligated to comply with lawful requests for data, such as subpoenas or court orders. This is true not only in Hong Kong but also in jurisdictions like the UK, EU, or the U.S., which have similar laws (e.g., the Computer Misuse Act (UK) or the Budapest Convention on Cybercrime). That said:

We do not proactively disclose data to authorities.
We aim to minimize the data we store and retain only what’s necessary to provide our service. You're also correct that simply stating we have servers in London does not fully address your concerns. While we currently manage server locations regionally, we are working on providing users with the ability to select specific data jurisdictions and one day be fully GDPR compliant. This is part of our future roadmap.

You can try to encrypt your files before uploading, as is something that some of our customers are doing, but this is tedious -- We do have a roadmap feature we're planning which is at-source encryption prior to upload, stay tuned on this.

Ultimately, it is takes a little trust in an entity that you believe has your best interest in mind and is providing a service that you find valuable. -- As we grow we do plan to address this more in our sales copy and allow our users to choose their data jurisdiction

Thank you for your support, and please feel free to reach out with any further questions or suggestions!