Web Scraping

  • Lisa Fröhlich
  • December 5, 2023

Table of content

    Web Scraping

    In the world of digital information, a fascinating technique can help us deal with the sheer quantity of information on the Internet: web scraping, which can be used to read and save data from websites. Also known as screen ccraping, the process is a powerful tool with applications ranging from the price comparison industry to financial analysis.  

    But how does it work? What ethical hurdles might need to be overcome, and to what extent does it tread the fine line between legal and illegal? 

    What is web scraping?

    In the age of digitalization, web scraping has initiated a revolution in information gathering and analysis. It is defined as the process of extracting data from websites and storing it for a variety of applications.

    Web scraping takes a peek behind the code curtain, which opens up extensive possibilities for data collection and use. The origins of web scraping can be found in the functioning of search engine crawlers, which were introduced in 1993. 

    The automated method has since found its place in the business world, whether for monitoring product prices or identifying relevant keywords in search engine optimization (SEO). In addition, the method provides sound decision-making aids based on data patterns and structured information.  

    How does web scraping work?

    The process begins with parsing, i.e., the logical reading of an HTML web page. This is followed by precise extraction of the data by powerful web scrapers. These programs scour the Internet, collect URLs, retrieve the desired data, and convert it into structured formats such as CSV or JSON files. Once the information has been converted into structured data, it is finally saved.  

    Automated tools, such as web crawlers and user-friendly web scraping software, make this three-stage process much easier. Techniques such as text pattern matching, data mining and HTML parsers are used to access and use information for a wide variety of purposes. 

    What is web scraping used for?

    This technology was established as an indispensable tool for companies that rely on data-driven decisions – from competitive analysis and lead generation to the development of innovative products.  

    For example, companies use this technology to gain strategic advantages through the targeted collection of product data in e-commerce or the analysis of customer ratings. In the financial sector, for example, it is used to monitor share prices and analyze financial data. It is also used in market research and science where market trend data as well as research data and publications are collected.  

    Is web scraping legal?

    The legal dimension of web scraping lies in a complex web of copyright law and technical protection mechanisms. In principle, web scraping is legal if it extracts publicly accessible data and does not infringe any copyrights 

    However, all those who use this technology should be vigilant. There is a risk of legal conflicts if technical barriers are circumvented, data is collected with user registration, or legal notices are ignored. In 2014, the Federal Court of Justice clarified that web scraping remains within legal limits if protective walls are respected and only publicly accessible information is collected.  

    However, the legal situation becomes stricter when personal data or copyrighted content is involved. It also becomes illegal if protective measures such as firewalls are bypassed. Ultimately, the legality of web scraping depends on various factors, in particular the type of data collected and the intended use. The handling of personal and proprietary data requires caution as data protection laws like GDPR introduce ever stricter regulations. 

    Spam and unauthorized SEO methods

    Although legitimate in many contexts, web scraping carries the risk of misuse for destructive or even illegal purposes. One such application is spamming. In this case, the technology is used, for example, to collect email addresses and send spam emails to the recipients concerned. 

    Unauthorized SEO methods are also problematic. One common example is the unauthorized copying of product descriptions by an online store from another website. This practice not only leads to duplicate content, which can have a negative impact on rankings in the SERPs, but also damages the page from which the content was copied. Webmasters should therefore be vigilant to recognize such cases in connection with their own pages and react appropriately. 

    How can you block web scraping?

    To prevent unwanted web scraping, website operators can take various protective measures to minimize negative effects, such as content grabbing or website performance degradation. Security precautions such as CAPTCHA tests, the integration of the robots.txt file, firewalls and targeted Bot Management are effective measures to protect against unwanted web scraping. 

    Compliance with data sovereignty laws and license agreements helps to maintain ethical and legal standards. In terms of the legality, the focus often lies in the way data is extracted from a website. Similarly, the enforceability of terms of use that prohibit web scraping is a crucial factor. It is generally assumed that scraping data behind a login is illegal unless expressly permitted in the terms of use. 


    Web scraping is an important tool for data-driven decision-making, as it enables efficient information gathering. The technology enables unique access to digital information, but requires responsible use, a clear legal framework, such as compliance with data protection regulations, and an ethical basis to justify its implementation. 

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