Twitter's official Transparency Report for July–December 2016 reported 489 censored tweets in Turkey from non-withheld accounts; the authors identified 6,402 unique censored tweets from the same period—approximately 13× more than officially reported—replicating an earlier order-of-magnitude undercount finding by Tanash et al. (2015).

41% of users (139,042 of 342,650) in the post-coup dataset voluntarily removed 18% of all post-coup tweets by switching to protected mode, deleting accounts, or deleting individual tweets; the largest groups were active users who deleted some tweets (44% of affected accounts) and users who switched to protected mode (22%).

§4.1, Table 1 policy

Zero pro-Gülen topics appeared in the public tweet set post-coup, while 70% of unreachable (deleted/protected) Gülen-related tweets were pro-Gülen; the unreachable rate for Gülen-related tweets was twice the background rate, quantifying rapid directional self-censorship on politically targeted content within days of a government crackdown.

§4.2–§4.3, Table 2 policy

Tor usage in Turkey spiked sharply during the initial days of the July 2016 coup—when ISPs were actively throttling Twitter—but declined steadily in subsequent months back toward pre-coup baselines, consistent with post-coup suppression being driven by chilling effects rather than sustained network-level blocking.

§4.1, Figures 2–3 evaluation

Comparing 5.6M pre-coup tweets (2015 Turkish general election) to 8.5M post-coup tweets (July–November 2016), the authors found 72% fewer government-censored tweets post-coup (142,492 vs. 513,719), with an estimated 43% of that decline attributable to reduced overall Twitter usage in Turkey and the remainder to user self-censorship.

§4.1 evaluation

During the June 2025 shutdown, Iranian authorities blocked international One-Time Password (OTP) SMS delivery, preventing new sign-ins to foreign secure-messaging platforms and VPN services. This forced users toward government-approved domestic platforms that lack security and privacy protections. The blockade of OTPs effectively weaponized account-recovery flows as a secondary shutdown layer, disproportionately affecting users who needed to activate new circumvention tools during the crisis.

2025-iran-shutdown-measurement §Human Rights Implications port-blockingdpikeyword-filtering

Simple character-level perturbations (English) and homophone substitutions (Chinese), combined with LLM instruction-following prompts directing the model to use word substitutions in its output, successfully bypassed all input and output filters for all 41 input-blocked and 197 output-blocked queries across five major Chinese LLM services (Baidu-Chat, DeepSeek, Doubao, Kimi, Qwen). Every input-blocked query contained at least one keyword combination that alone triggered the filter, confirming keyword-matching rather than semantic classification.

2026-ablove-characterizing §VII-D keyword-filtering

Cross-national experiments conducted from Singapore, South Korea, and Taiwan during February 19–24, 2025 found no variance in blocking implementations, event syntax, or server infrastructure across all five Chinese LLM services. Input blocking was enacted identically in all three international locations, and services connected to the exact same server IP addresses globally — Kimi and Baidu-Chat connected to identical IPs and DeepSeek to the same two addresses across all tested locations.

2026-ablove-characterizing §VIII-A keyword-filtering

Input blocking in Chinese LLM services (DeepSeek, Qwen, Kimi, Doubao) is overwhelmingly consistent: all four services persistently block the exact same queries across all 5 measurement samples in both Simplified and Traditional Chinese. Output blocking is far less consistent, with only 29 out of 349 output-blocked queries blocked across all 5 samples. Baidu-Chat is exceptional: it performs almost no input blocking but instead relies heavily on post-search and output blocking (78.6% of blocks are output-phase).

2026-ablove-characterizing §VI-B keyword-filteringdpi

DeepSeek, Kimi, and Doubao all transmit analytics logs to the same Autonomous System (AS24429, Zhejiang Taobao Network Co., Ltd., a ByteDance/Volcengine subsidiary), with one monitoring endpoint IP directly overlapping between DeepSeek and Doubao. Additionally, all four non-Qwen services maintain connections with servers physically located in China throughout the chat session, transmitting user IDs, session IDs, viewport data, language preferences, and in Baidu-Chat's case, the full query text via URL-encoded CAPTCHA requests.

2026-ablove-characterizing §VI-D keyword-filtering

All five Chinese LLM services transmit partial or complete responses to the client machine even when output blocking is triggered, representing a major information leak. For DeepSeek and Qwen, truncated blocked responses are on average close in token length to full successful responses. For Baidu-Chat, the complete response is transmitted to the client but only partially rendered in the browser UI, with only a word or two visible on screen.

2026-ablove-characterizing §VI-C keyword-filtering